we got the issue, other clients were facing the same issue since the last update. There was a bug and we fixed it. Now please update to version 6.6 in a few minutes and everything will be perfect. Thanks for your patience.
I got the same problem. I updated both fee to 6.6 and “Bulk Product Sync with Google Sheets” (this is the new Pro?) to version 6.1. Everything was connected and I got no error when fetching products, but nothing showed up on the sheet.
Problem was in our default setting for sharing sheets -> I had to allow editing of the sheet for everyone who has the link, as this was restricted to “watch only” as default.
I hope this will help someone if they face this issue again.