Bug Report: wrong collumn number

I have a issue with a formula in the datasheet ,

The formula in sheet is correct and functional but when new data has been placed, the formula come different, to be more specific, is a error in the collumns number. The sheet understands collumns numbers as letters (A,B,C,D…) but instead the new data come with (C1,C2,C3…), and with this the formula dont work correctly. I have the same formula in other sheets and this problem dont happen.

AppSheet converts your formulas from A1 to R1C1 format.
For more details see this article https://help.appsheet.com/troubleshooting/issues-with-specific-providers/issues-with-google-sheets-formulas

The two formats are completely equivalent.
It is possible to convert from one format to the other in either direction with no loss of information.
For more details Google “A1 versus R1C1 formula format”