Google spreadsheet integration stops

I've started tracking our issues with google integrations.  I realize that within the last year we've had at least 3 forms that just stop being integrated--submissions are no longer being recorded on the google sheet.  They are forms that are long-term in standing that we haven't made any changes to.  Could you help me understand what would cause these breaks?  I would appreciate any ideas you have.  

Thank you.  

We had some temporary issues with the google spreadsheet integration which is most likely the reason of stopped syncing. To restore the spreadsheet syncing you can:

1) Re-integrate your form with the google spreadsheet service. It will create a new spreadsheet with complete form data.

2) If you need to update current spreadsheet, you can add some new field to the form or re-name any current form field. The integration will reset the spreadsheet with the next received submission.

If you need any further assistance, please let us know.

I am curious if your "temporary issues with the google spreadsheet integration" happens occasionally? In my research we've had the exact same problem around the dates of 11/9/15 and 1/31/16. 

Unfortunately, it might happen since there are a lot of factors involved. Although, we keep working on making the service and integrations as stable as possible.

Thank you for the response.