Submission data of form is not being saved to google spreadsheet.

However, now I'm noticing my form - which was supposed to
automatically populate to a google sheet - isn't doing that. And it also
wasn't clear to me that integration of payments was $19/month. I'll remove
the payments feature. But I am curious about the sheet not getting
automatically populated?

I'm sorry for the trouble caused to you. 

Did you make any changes in any of the column header of your integrated google spreadsheet? Please note that editing column header will cause the integration to break.

I have synced your google spreadsheet again. I would suggest you to please check your google spreadsheet and see if the missing submissions are being displayed or not. If the issue persists, I would suggest you to please remove the existing google spreadsheet integration and then integrated again.

We will wait for your response.