This cannot be your whole code as WepShoppe_wmb is not defined. Apart from that I don't get the point what this code is supposed to do. By the way: you never assign anything to on_1 so the engine won't do anything at all when you press "1". Hence there is no need to unassign the key later on.
First you wait until the player gets closer than 100 quants. Ok so far. Then you wait a second - no idea why - and load a new level. Later on you try to check if "1" is pressed.
if(key_pressed(key_for_str(key_1off)))
This seems dangerous to me. Note that key_1off is ambiguous. It's a var as well as a STRING*. Not sure if Lite-C detects that the string is required or passes the var to key_for_str. I'm afraid it's the latter one and that may cause trouble.
Finally you try to remove the "my" entity which should be removed anyways through level_load.
Maybe you describe in more detail what you want to achieve?
