Calc does not correctly calculate Sum formulas in some cells

I have a worksheet using multiple formulas that affect a single cell. I setup a Sum() to subtract from a cell with a set amount, but for some reason it doubles the number.

The cell’s formula is: =4000+G7-Abilities.B14-SUM(H15:H33)-Calculations.B9-SUM(C15:C35)+Calculations.D21-H15

Currently, this one cell seems to double when I add a 1 to it. The problem might be in the actual formula cell, because it only doubles when H15 is subtracted. I am using the template file format if that makes a difference. I’ve attached the worksheet. The file should be attached, but I got an error. “Type Error: Data is undefined”. Sorry, I couldn’t upload the file.

Sorry I can’t see the attached.

Maybe the problem is in some cell the number is introduced as a text, then SUM() don’t use it.