My phone screen black but still vibarate

I get this 2 time before and it because the screen broke, the first is broken screen second is loose screen connector, but this time it diffrence it vibarate when i do a soft reset or i just hold the power button but i cant call it and the gps is not working when i use find my phone app and i cant play sound, when i reset it it flash the screen and viberate for like milisecond and then nothing. It my Mom's phone, and she says it just suddenly dont start.

I already charged it, and i already plug in to reset