Discovery not working

Hello community,

i try to connect openHAB2 to my sonos PLAY:5 with the sonos binding using the Paper UI but the inbox shows no device after a search. Also binding the device manually did not work. It shows “online” for a short time but switches back to “offline”. I installed GUPnP to see if there is maybe a problem with my network but the PLAY:5 is shown there. So i am wondering if i forgot to set up something. Hope you can help me.