Fruit Machine Chat

i can see the lock, but it doesn't open. There's a little black pin like thing next to the lock but i cant move it.

i can see the lock, but it doesn't open. There's a little black pin like thing next to the lock but i cant move it.

Help Please, i've just brought The Pots Of Gold machine and cant seem to get the top door open, im sure im doing something wrong, but i have no idea as to the workings of a fruit machine!!