There was an issue with saved data in online storage.
Sign in to PlayStation Store, select your avatar, open Subscriptions Management,and check that you're subscribed to PlayStation Plus. You need to be subscribed to PlayStation Plus to use online storage.
Restart your console.
Make sure that your online storage data doesn't exceed 100GB.
Make sure that the number of saved data files in your online storage doesn't exceed 1000.
Go to Settings > Account Management and sign out from PlayStation™Network. Then sign in again.
Go to Settings > Account Management andselect Activate as Your Primary PS4.