Imran,
Unfortunately that isn’t something I can fix. This is a limitation on the part of HubSpot…
The oAuth authentication token from HubSpot is only valid for 8 hours.
We use WordPress’s CRON to request a new authorization token before these 8 hours are up. Unfortunately, WordPress’s CRON requires a user to visit your website… So if you go more than 8 hours without a visitor visiting the site, there is absolutely nothing I can do about it, and the token expires.
A current in-place work around it is by not using oAuth, and using the “API Key” method instead. You can get an API key by going here: https://app.hubspot.com/keys/get
It’s frustrating and I wish there was a way around this with oAuth, but there isn’t. The only other way I can work around this is by building a CRON that can run on your server, but that requires an extra admin step (cPanel, Plesk, etc), that most WordPress users aren’t familiar yet, and potentially don’t even have access to. I will consider adding it in the future, at least so it’s an option that’s available.
-Chris.