How can I stop Jotform from resetting a Google Sheet?

I am using the google sheets integration on a few of my forms to manipulate data. Unfortunately, when I alter or add the form questions all of my other sheets and manipulation are deleted. How can I stop this?

You should rename the sheet to something different than the file name generated in Jotform, this way the integration will not overwrite the file at google.

If I do this new submissions will not be added to the existing sheet and a new sheet is created. This does not solve my problem.

When you add or alter the form, the spreadsheet is refreshed to make sure that the new fields will be added in your spreadsheet. Unfortunately, I believe this will reset the changes you are directly making on the spreadsheet. 

Constant changes on the form will most likely messed up the spreadsheet data and the layout of it, this is because columns are added/deleted. So we usually recommend re-integrating to make sure that form is properly sync on the spreadsheet. I personally do not recommend making changes directly on the spreadsheet, I usually suggest users to manually create a separate spreadsheet and use a function like IMPORTRANGE to reference the values on your integrated spreadsheet. The manually created spreadsheet is where you can make changes like manipulation, added formulas, comments, etc.. Here's a link about the IMPORTRANGE function: https://support.google.com/docs/answer/3093340?hl=en. With that, we don't need to directly make changes on the integrated spreadsheet. The changes in your spreadsheet won't also reset because it is a separate file and not directly integrated to JotForm.

I hope that helps.