Ps4 Pro error code WS-36768-0?

Today I bought a Ps4 Pro and yes how should I say it there's always this code when I go to the friends list and a friend of mine said that my user doesn't exist at all. Does anyone know what it is and how it goes away?

WS errors are actually Playstation Network errors.

Probably a connection problem with the PSN.

Did you register correctly if you only have it since today and is your internet connection working?

I think I signed up there was something with the family manager, but I think that's not the reason. Internet connection is also good. Do you know how to fix it?