Inventory synced but incorrect

The client has now reported numerous instances of inventory level discrepancies, these seem to be occurring most often when a purchase is made in Zettle but many times the inventory levels are already wrong between the 2 platforms prior to purchase. Their most recent report is as follows:

Website said we had 11
Zettle said 46 (we have 46)
I bought 4 online
Website changed to 7
Zettle changed to 7

Log states Attempting to update stock of product 6073 with an amount of -36

WordPress, WooCommerce and this plugin were all on the latest versions (5.8.2, 5.9.0 and 1.5.2 respectively), the latter of which was updated recently so I’ve rolled it back to 1.4.2 in the hopes that will improve things.

Need input from your end regarding how to proceed ASAP.

Hello @matthewdixon

thank you for reaching out to us, we are here to help.
There are 2 situations that can cause this that we have identified.
1) Other plugins adjusting stock count.
2) Hosting firewall settings cause webhooks to fail.

Let me answer both cases:
1) In the past we have seen other plugins that also have a stock adjustment function that could cause malfunctions in the stock updates. Sometimes they would avoid the change or they would cause multiplications of the changes.
2) your situation sounds more like the webhook issue. It seems that the updates that need to come from Zettle to WooCommerce are not going through. We have been seeing this in some cases where the webhooks for this activity are being blocked by the hosting provider’s firewall. I have looked at the webhook logs that we have access to and see multiple entries for this website (redelephantbeercellar.co.uk/), so I would start by contacting your hosting partner to have this reviewed. In one of my last cases that we got resolved the merchant informed us the following:

It may seem that PayPal’s server, which is trying to contact your web site via webhook, has ended up in our automatic firewall due to the large number of requests.
I have removed these blocks now, and will look at the possibility of adjusting the filter so that these are not caught again.

Please see if you can do the same.

Kind regards,
Joost

Hi Joost,

Thanks very much for the info, that’s really helpful. There are no other plugins on the site which could be interfering with the stock levels so I think it’s safe to assume number 2 is the culprit! Hosting support say there’s nothing on the server that could be blocking traffic but there are 2 other possibilities: Cloudflare and Wordfence.

Cloudflare – are you aware of anything here which could cause this issue? There are options here to add firewall rules.

Wordfence – there are options to whitelist IPs and URLs, could you let me know what would need whitelisting? I’ve disabled the plugin completely for now but would like it enabled in the long run.

Kind regards,
Matthew

Hello @matthewdixon

we are not aware of any issue with these 2 plugins, but you should be able to test if one of these 2 is the culprit or not, right? You could deactivate them and test manually if the issue still is there.

Regarding the IPS’s/URL’s, we had this question before, but the answer is not that straightforward, since Zettle is hosted on AWS and there is no 1 IP or range for this. We have to advise against using IP ranges, but if they want to they need to add the whole AWS IP range for region eu-west-1 from here: https://docs.aws.amazon.com/general/latest/gr/aws-ip-ranges.html
Using such a broad range doesn’t give any real value and probably won’t fix your issue (as we saw in previous instances of this).

Let me know if you get any results on this.

Kind regards,
Joost

Hi Joost,

Testing this won’t be easy, manually updating stock levels on either platform has never been a problem, we’re seeing the issue when a purchase is made and each case it looks like the stock levels were already out of sync prior to the purchase. The only thing I can do right now is deactivate Wordfence and cross fingers which is far from ideal.

I have removed these blocks now, and will look at the possibility of adjusting the filter so that these are not caught again.

Who was this quote from? How were they able to remove ‘these blocks’? If IPs aren’t going to work is there a domain the requests originate from that could be allowed?

Hello Matthew,

This response was from the other merchant that was contacting us when encountering similar issues.

Just to clear up the situation: you are not able to reproduce any issue by manually adjusting the stock in Zettle? In the related cases, the merchants can normally reproduce the issue when adjusting Zettle stock (and WC stock does not sync to that change).

When I reviewed the webhook notification, I see that these notifications are all concerning 1 product, this product has got UUID 64f0e1fa-9ba4-11eb-a084-3347a5462f41
Maybe you can take a look into that product and see what is causing that to encounter issues?

However, stating before that this is not as clearly related to our known bug with the hosting partner (if you confirm my statements above), then it would indeed be best to continue looking into the plugins you are using.
If you want us to take a look, it would be best to get the system report and Zettle logs. You can copy the logfiles from here:
– WooCommerce > Status > Get system report > Copy for support
– WooCommerce > Status > Logs > select “zettle-pos-integration-\[…\]” in the dropdown and click on view.

If you don’t feel comfortable sharing those details on a public forum, please open a ticket with our service desk. You can find the instruction for this here: https://zettle.inpsyde.com/docs/request-support/
(please add the URL of this thread in the ticket as well)

Kind regards,
Joost

Yes to confirm when I manually update the stock levels, either on the site or in Zettle, the other platform reflects this change pretty much instantly (this is just my experience and I’ll check with the client but they’ve never complained of it not working).

Issues from them are coming in thick and fast, they’re all over the place:

I don’t know if you need/want any more examples but the Verdant – Italian Pilsner (we have 6) has suddenly shot up to 15! Changing it back to 6, but yeah… it just seems like it is happening to random items.

Oh christ, there are so many new items that it’s happening to! ??

I’ve generated the report with the current plugins but am going to roll them back to their state before I did the latest maintenance updates. I don’t think any other plugin on the site could be interfering but I’ll send over the system report and logs.

Regarding the previous comment of ‘I have removed these blocks now’, can you let me know what this refers to? Maybe it will be helpful in this case if a URL can be whitelisted or something?

Also, regarding UUID 64f0e1fa-9ba4-11eb-a084-3347a5462f41, how can I tell which product this is on the website?

Kind regards,
Matthew

Morning fellas, me again!

I was wrong above, editing inventory levels in Zettle manually does not sync with the website, but crucially it does with Red Elephant’s sister site, Green Elephant!

These sites are pretty much identical with only a few styling differences. They have the same plugins and both run through Cloudflare, so we now have a working setup (Green Elephant) to compare against.

I’m using the same product on each site to test with:

https://redelephantbeercellar.co.uk/product/la-trappe-blonde/
vs
https://greenelephantbeercellar.co.uk/product/la-trappe-blonde/

Manually updating the stock level in Zettle works perfectly for GEBC but not at all for REBC. Both update fine if the level is manually changed in WooCommerce, so the issue is communication from Zettle to the website on REBC only. Please could you look at things your end to see why this works for one and not the other?

Looking at the logs I see this reference on GEBC:

2021-12-11T09:33:12+00:00 INFO Received Webhook: InventoryBalanceChanged
2021-12-11T09:33:12+00:00 INFO Attempting to update stock of product 816 with an amount of -1
2021-12-11T09:33:25+00:00 INFO Received Webhook: InventoryBalanceChanged
2021-12-11T09:33:25+00:00 INFO Attempting to update stock of product 816 with an amount of 1

But nothing similar on REBC, the only reference to Received Webhook: InventoryBalanceChanged is:

2021-12-11T08:35:05+00:00 INFO Received Webhook: InventoryBalanceChanged
2021-12-11T08:35:05+00:00 INFO Ignoring InventoryBalanceChanged event since it was triggered from our plugin

(I assume this is from me changing the stock level on the website, the odd thing is I’ve changed more than one on the website but this is the only reference to Received Webhook: InventoryBalanceChanged)

Kind regards,
Matthew

Thanks Matthew, as informed on the Service Desk ticket, it looks like there is an issue ongoing, since I see more people having this issue since last week. I have created a bug for our developer to take a look and I will add these details to this bug.

If you did any further testing or can tell me more details on where these 2 sites differ, please do so (here or in the SD ticket).

Thanks again for your support.

Kind regards,
Joost

Hi Joost,

Leaving this comment here as might be relevant to others in the future. The main difference between REBC and GEBC is their age, REBC where we have the problem is a year or so older. A thought occurred to me that this could be an issue with older API keys not having the correct permissions, so I created a new one for REBC and replaced the old one on the site. This hasn’t made any difference, manual inventory changes I make in Zettle are still not reflected on the site and I keep coming across discrepancies which I’ll detail and to the Jira ticket.

Kind regards,
Matthew

Hi again Joost,

Just wondering if you could confirm one thing to be absolutely clear – when updating stock levels in Zettle > Products > Inventory, should this update WooCommerce? Looks like it works perfectly on GEBC, but I don’t think it ever has on REBC..

yes, that should be the case. That is how I tested this issue to occur on another merchant’s staging site when I connected it to my own Zettle account.

And you saw the same behaviour on a site experiencing problems? Ie. manually changing stock in Zettle failing to update WooCommerce?

I wonder if this is the case for all the other merchants experiencing issues you mentioned in the Jira ticket, if this is a pattern it could be key to finding the issue.

I only have 1 other site that was able to test on, but yes: when I changed the stock for variation of a product, other variations of the same product were changed in different amounts on WooCommerce.

Hi @joostvandevijver,

Any progress on this one? Have Zettle shed any light yet?

Just had an update from REBC that they have checked through WooCommerce and they ‘would say that 70% of the stock levels are wrong’ – which equates to hundreds of products. This is causing them all kinds of headaches and is incredibly frustrating for me as I’m not sure what else I can try my end, other than doing a fresh sync of products from WooCommerce to Zettle – do you guys think this is worth a go? I imagine the issue will persist as looks like it’s on Zettle’s end but if you think it’s worth a go we can try it..