problems streaming spotify on Sonos device

[Niquila]

Hi, 

My account has changed from one month free spotify premium to spotify premium payed with KPN, this is my telephone company. 

With switching the accounts my spotify does not stream any music anymore to my Sonos device. I have called Sonos and it seems to work with another Spotify account, except my own, this was also a KPN spotify premium account. 
I can enter Spotify in Sonos, but I cannot stream. I have tried already everthing (updating, install again, verify spotify with sonos again), but nothing works.
Can you help me with that?

[Peter__]

Is your account definitely showing as Premium on your online overview?:
https://www.spotify.com/account/overview/