Phone has completely stopped responding - How I can fix it?

[AC Question]

My phone stopped working suddenly. Now it won't start or go into Recovery mode. It has non-removeable battery.
Connecting the charger doesn't show anything. When I connect it to computer, "USB device not recognized" message appears.

Any suggestions?

Phone: Infinix Zero3
Android: XOS- Chameleon V2.2

 

[belodion]

Battery failure, perhaps, or a failed battery contact?