So is People the sheet name, do you have a name column and a role relation column at all?
In my experience, I’ve gotten this warning under two scenarios. One is when manually removing a column from the sheet that was still being used by the app, and another is when using some kind of formula (for example ImportRange), which generates the column, including the header. In the second situation with the formula, sometimes glide will be syncing while the formula in the sheet is running and the column is temporarily not present. In both cases, Glide will see there is a column missing and issue the warning. In my experience, restoring the missing column does not cause Glide to begin syncing again. It’s like it’s stuck and refuses to check the sheet again for the column. In my case, I’ve had to go through the entire app and try to find anywhere the column is used. Then I’ll temporarily reassign the component to a different column. Then I’ll click on reload and let Glide do its delete, hoping I didn’t miss anything and hoping nothing actually gets deleted. Once Glide is syncing again, then I’ll revert any components back to the intended column. It sucks, because there is nothing in the warning to indicate where to look for the affected components. I have so many parts of my app intermingled and it’s scary to let it delete something you had no intention of deleting and may not know where to look for it. The warning does say that restoring the column will fix the issue, but I have yet to see that work. Once a column is seen as missing, even for a minute, the app is DOA until you fix the issue. I’ve even had data loss because the app and sheet couldn’t resync, and data enter by the user disappeared, even though the issue that caused the reload warning resolved itself. I’m now a little more careful to make sure any headers created by some formula or script are actually entered myself manually and the formula is only pulling data into row 2 and below, instead of the headers along with it.
Long story short, your best bet is to find anywhere you may be using any of those column names, temporarily reassign them to a different column, click on reload and cross your fingers nothing actually gets deleted, then revert the components back to their original column. You may have fixed the issue, but Glide is glitched any won’t resync until you let it delete what it thinks it needs to delete.