Can't take damage!

Help!

I’m playing garrysmod on single player and I can’t take damage at all, I can’t die!

I don’t have god mode on.

I checked the utilities and god mode is not on there.

UPDATE: I can’t take damage ONLY in the Half Life 2 maps, why is this?

Turn sbox_plpldamage to 1 and sbox_godmode 0