RetroArch - PS1 Metal SlugX cannot start 1p game

RetroArch - latest from Playstore / Core - PCSX ReARMed / Controller - Shield controller Game - Metal SlugX (PS1)

Can’t figure out how to press 1p for player 1 to start I have no problem using all the buttons in other games (ie; Colony Wars) Maybe someone can fire this up and help me out