@hristo-sg, I just reported the same issue to Siteground support. My WooCommerce status report shows a small dollar amount which is incorrect for the month. Within WooCommerce reports, For last 7 days, there is a $0 amount. There are orders and I sometimes can see the monthly sales properly when refreshing browser and/or clearing cache. I even turned off SG Optimizer all together and that does not fix problem. Up to a few days ago, clicking purge sg cache appeared to fix it. I have an open ticket to Siteground support, but no resolution yet. I even created an exact copy of the site on Siteground staging and I cannot recreate the issue in there. Problem did seem to appear after latest SG Optimizer update. Here is what I have done thus far to attempt resolution.
*As soon as I recognized the issues, I created a Staging copy of my site to test. As soon as that loaded the reports on staging copy, the reports were working. So, there is essentially it does not appear to be any problems on staging copy. I was going to test in staging by disabling plugins/changing themes, etc. But problem does not appear.
*I also looked up Woocommerce caching configuration and setup caching as close to possible as stated in this document. https://docs.woocommerce.com/document/configuring-caching-plugins/. It did not make a difference
* I tried clicking Purge SG Cache again then reloading report. That does not work. For example, it shows $0 for last 7 days. I verified paid sales today under WooCommerce Orders. I even cleared my cache, history and every saved settings in Chrome browser. I then tried in Firefox. Same issues. I did not turn off SG Optimizer, as I was not sure what that would so with my SSL config.
* Then, I disabled caching in SG Optimizer EXCEPT “Enable HTTPS” option. Then I clicked on “Purge SG Cache” in WP admin just to make sure it was clear. I then cleared my browser cache, closed Chrome and reopened. Signed back in the WP Admin page. That seem to fix part of it,so it confirms a caching issue. The Net sales for month under the Dashboard WooCommerce status now shows a the current monthly sales amount. When I go into WooCommerce Reports, and click on “Last 7 days” view, it shows a zero sales amount. Obviously, there are sales in last 7 days, as I had a total for current month. So, it is partially working now.
*Next, I placed the website into maintenance mode and completely disabled SG Optimizer. Reports for last 7 days still do not populate. I also changed themes to see if it was a theme conflict. I use a Divi child theme. I switched to Twenty Nineteen and still same issue.
Something appears to be stuck in the back end. I had to re-enable caching for site performance, but I do not have memcached enabled at this time, due to this post. Just posting to let you know others are having this issue. I also posted this info in WooCommerce support forum.
