macbook blinking question mark folder after bump

macbook was in sleep modus.

apparently i hit my backpack somewhere and it has a bumo.

opend it, was just really unresponsive.

turn off

turn on

blinking folder with question mark

i put another working hard drive inside and the problem sussists

now the bump is on the opposite part of the hard drive location

what part is damaged ? it may be the cable to the hard drive.

somebody had the same issue?
these hitlers want 29 euros just to talk with me at the telephone, i hope the community can be more helpful