Buttons not working for ROMs

Hi there. I just built up my Picade and loaded my first ROMs (Amiga/ amiberry). Now my buttons are all mapped and they function just fine when hopping through the Picade and Retropie menus. When I start an Amiga game/ ROM neither buttons nor joystick work anymore. I tried to find any settings, but cannot find any apart from the global button mapping. Anyone had the same issues??