won't turn on

I had a Unimax U504TL smartphone and used a free firewall called Firewall No Root by Protectstar Inc. on from the play store. The firewall would turn on just fine when I turned on the phone and tapped it to turn it on. It wouldn't turn on automatically with the phone like it said it would for...

My mom and dad had two old HTC Desire 510 phone sitting in a drawer and asked me to help them erase their personal information and recycle the devices. One device works without issue and erasing was a breeze. The other, however, seems to be completely dead, however. What I know: No matter...