[iOS] Spotify doesn't connect without restarting the app

[xgymclass]

I have a problem with the Spotify  iOS app on my iphone: I always have to completely restart the app, otherwise it doesn't connect to the Internet ("there seems so be a problem...").

iOS 11.2.1

Spotify 8.4.28.1104

I have: 

- restarted the phone

-clean installed the app

-restarted the router

-tried it via Wifi and LTE

- logged off and on

Nothing has fixed it so far and it is REALLY annoying.