How to turn off the "Screen Overlay" setting? I'm using the Oneplus 2 and last week I updated my phone's software and ever since then I'm not able to do much on my phone. I'm not able to download photos on WhatsApp and neither am I able to send someone photos. Only one message keeps on popping up saying "screen overlay detected go to "App Settings" and turn it off". I tried following the instructions and turned it all off, but it was of least help. If anyone here has any clues about it, please help.
Got insights from multiple answers here and other forums . 

Consolidating how I got rid of the issue : 


Go to Settings > Apps > (your app which is getting issue)
Press on Power button till window for Power off , reboot , airplane mode comes up
Hold on Power off option 
Select reboot in Safe mode 
Go to settings > apps > (your app which is getting issue) 
Select whichever permissions you want 
After Android M update , issues can come up in apps like Messenger , Whatsapp , Prisma etc. 


Let me know if any issues . 
Note : I am having One plus One mobile.