Connect 4: Run-time check error #2

[FlyingWolFox]

When running, certain games will cause this error after the tie verification runs

[FlyingWolFox]

Got a trail to the issue. So these order fo inputs make the check fail:
1, 2, 3, 4, 5, 6, 7, 1, 2, 3, 4, 5, 6, 7, 1, 2, 3, 4, 5, 6, 7, 2, 1, 4 , 3 -> Fail
TL;DR: 1-7, 1-7, 1-7, 2, 1, 4, 3 -> fail

Other combinations also does this, but this is the easyest to get

Still no idea what is the problem.
I'll disable the minimax algorithm and change the tie system...