That only happened to me today. 1 hour ago everything went normal I had played the game fifa 19 but then I wanted to go to YT where the loading screen with the YT logo was loaded, after that I was on YouTube menu but it was as if my controller it would be over, I couldn't do anything on video, or switch video, circle, x, triangle didn't work either from the moment I restarted my ps4 it was normal in the menu I go back to YT / Twitch and the same thing happens I don't know if this is my controller or my PS4
AN HOUR AGO, EVERYTHING WAS NORMAL
And weekend…
And don't waste your time criticizing my German, I already know…
Have you ever tried to reset the controller? If not, there's a small hole near L2 that you should be able to get in easily with a paper clip or something similar. Then hold the button down for about 5 seconds, pair the controller with your PS4 again and see if it works.
If that doesn't work, try a different controller and if that doesn't work either, it's most likely due to the ps4 or the YouTube app itself. Simply delete the app and download it again.
Prix90210 wrote a good answer.
What I can think of would be that your controller was completely empty at that moment and therefore went out.
