[Riddick94]

Go to the checkpoint and try to stand in center of it and check your coordinations. You can compare X, Y (of your position) to the checkpoints you have got in your gamemode, or simply check Z height of both positions. That SHOULD be your checkpoint.

Otherwise, try commenting SetPlayerCheckpoint lines in your gamemode, and check in game.

P.S
That's why you should've ALWAYS comment everything what seems to be important.