Why is my phone turning on and off?

[nchigilbert wamTv]

All this happened when i downloaded an app they asked me i needed Google play service to open the app since then my phone went off and hardly come on fully again. the mark of my phone is Samsung Galaxy S5 mini. Please i really need help.

 

[Ian Morgan2]

What app did you download ?

 

[B. Diddy]

Welcome to Android Central! Tell us the exact name of the app you installed, and if you installed it from Google Play Store or somewhere else. What happens if you uninstall the app?