Try wiping the cache partition on the phone and that should resolve the issue. To do this, just search 'how to wipe cache partition S8' and you should find what you are looking for 🙂. Hope this helps! 😎
have you tried to restart the phone? If so, please remove your Samsung Account from Settings> Accounts and back up> Manage account> Select the Samsung one> Remove account. Once done, re-add the account from the same path.