Indexing is changing formula

I have a sub that sorts a range.
After sorting I discovered that one of my formulas was changed.

The range being sorted is Sheets("Teams").Range("B10:DP18")
The formula in M10 is:

=IF(ISNA(L10),0,INDEX(Players!Disabled_Matches,Teams!L10,1))

After the sort, Cell B10 was moved to B13, and my formula in M10 was:

=IF(ISNA(L10),0,INDEX(Players!Disabled_Matches,Teams!L13,1))

The rest of the formulas on row 10 continued to point to cells on row 10, but part of this one pointed to the new row.
And the rest of the formulas in column "M" were changed accordingly.


Edit

I just discovered that the formula in N10 remained OK

=IF(ISNA(L10),"",INDEX(Players!Player_id,L10,1))

Edit Again

I found the answer. Having "Teams!L10" was the problem. When I just had "L10", it remained ok.