Chosen Solution
My iPhone fell yesterday. since then the power button as well as volume and silent buttons are not responsive (its locked on silent). Also the headphones don’t work anymore. On a related note already that whenever I’d pull out the earphones, for a brief moment it would show no service/ no sim (i suppose it was dislodging the sim)
Ok I figured it out by myself. Opened the iphone up, I found that the number 5 ribbon was diconnected,just putting it back into place and all buttons are working again.
