How do I fix my intall button?

[AC Question]

I have an Blackview A5 and in it an android marshmallow.And like from 10 months it worked very well,and now one say when I wanted to install something from 1Mobile Market,when all apk downloaded and it was only left to click the install button,it didnt workes when I clicked it.I kept clicking harder but it didnt work,the cancel button worked very well.I searched for this problem and a lot of people had it,from some screen filter they downloaded for brightnes and they just turned it off and it worked.I dont have any screen filter,how do I solve this problem,please anwser.

 

[belodion]

Try Safe Mode. https://forums.androidcentral.com/showthread.php?t=409154