lock buttom and middle buttom is not working my handset is samsung j7 next

[Android Central Question]

my handset is j7 next power on n power off is not working and the middle buttom is not working

 

[B. Diddy]

Welcome to Android Central! I assume you mean the Home button when you say "middle button." Does this persist after a reboot, or in Safe Mode? https://support.t-mobile.com/docs/DOC-30290. If so, it's probably a hardware problem -- bring it to a repair shop.