hfebgjh Welcome to the community!
Please try the following:
1. log in to the portal under this link.
2. change your “mobile number” - you can also enter a landline number. The system does not check the number.
3. Wait in the portal until the new number is visible. This took about 5 minutes. Just load / reload the page several times.
4 Change your password.
5 Log in to Sunrise TV with the combination landline number/new password.
6. change the landline number back to your mobile number.
Does it work afterwards when you log in with the phone number?
Greetings
Daniele