Do you mean the following error: Your access token has expired. This application uses OAuth 2.0 to Access Google APIs. Please insert the information below and authenticate token for Google Merchant Shop. Generated access token expires after 3600 sec.??
Well, you are getting this access token expired message due to the security measures from Google. This session automatically expires after 3600 seconds.
However, you won’t have to be worried about this message as you only need to authorize before submitting your feed to Google for the first time.
Once your feed is submitted to the Google Merchant, you won’t have to authorize again unless you want to submit a new feed or make any changes to your existing feed structure.
Let me know if you face any issues.
Thank you.