Which Joystick model do you have?
Hold down fire button for 1 sec. to enter/back game menu.(regular Joy for Atari/C64, with 1 fire button. They may have more fire buttons, but they are all connected to one pin number 6 )
BTW
diagram for proper 3x Button Joy C64GS:
Viewing post in Briley Witch Chronicles (C64) comments
I see. OKAY.
I can only advise this:
-plug the second FIRE to pin no.2 (direction DOWN in Joy port 1)(disconnect from pin No.6)
-in the game, set the menu to be under the [<-] key (arrow pointing left)
the downward direction (activated with the second Joy button) on Joy port 1 will open and close the menu
xD
Ps
I assumed that you made this custom Joystick yourself.
+1