Linphone OK on ubuntu PC ... but not on S9 /e/

I’am struggling since 2 days to setup linphone on my S9 .
My SIP provider is switzernet
To mitigate doubts i try to configure

  • gigaset C450IP on my LAN : connection works fine
  • Linphone PC (ubuntu maté 20.04 ) on my LAN : connection works fine

I try also to force S9 linphone thru home wifi , not 4G , because some (damn) cell phone providers locks port 5060 , … still connection impossible :hot_face:

So i can say that

  • my SIP provider account is OK
  • my LAN and router are OK

Any idea would be welcome …

Regain your privacy! Adopt /e/ the unGoogled mobile OS and online servicesphone