Silent mode keeps on and off all time

I got a new iphon 14 pro and i lunched it every thing is good. After 1 hour i do a facttory reset in ordar to move data whatsappp frim android to iphone. After the factory rrset the iphone siknet mood keeps on and off all the time. If i turn the trigger to mute its stay muted. And when i unmute the trigger and started again doing silent unsilent