Step 1. Go to: https://myaccount.google.com/permissions
– Delete any PlayStation associations related to the account you are trying to connect with your youtube app.
Step 2. Create a new PlayStation network account and log into it on your PS4.
Step 3. Go to:
– PlayStation Network/Account Management
– Link with Other Services
– Click on YouTube and sign in with the Google account you are trying use on your primary account. (This will break the permissions link from the improper break to your primary account before which caused this issue)
Step 4. – Now, go into your primary account and open up the youtube app (It should be working) then close it.