If the factory reset process doesn’t fix your problems – or doesn’t work at all – it’s likely that there’s a problem with your device’s hardware. If it’s still under warranty, you should have it fixed or replaced.
(There’s one exception to this: If you’ve been flashing custom ROMs and messing with your device’s low-level software, it’s possible that you could have overwritten the stock recovery software. In this case, it’s possible that you have a software problem and not a hardware problem.) |