[Script] How to make a script tile not freeze

I'm scripting a event in Mt. Moon but when I assign it to a green script tile in Amap when I go to it, the game locks up. Is there anyway I can fix this?

Set the value in the value bar to 0

It needs to be equal to the value of the var, which by default is 0

And then you can change the value of the var to 1 when the script is done, that way it doesn't run again

It needs to have a var number too, like 404B, for example, there are lots to use check what they do here https://www.pokecommunity.com/showthread.php?t=302347