Teams SIP Gateway connected phones and voicemails

[MK_ASK]

We have a strange issue. A Teams user got a new SIP device that is successfully integrated via SIP Gateway. If a caller leaves a message, it will appear as a voicemail in Outlook, all Teams apps and devices. The SIP device also shows that there is a new voicemail, but if we want to listen to the voicemail and press 1, we get told that there are no voicemails.

Do we need to change or add anything in the configuration?

Regards,

Matthias

[#2]

I also reached out for the Microsoft support. The suggested solution is to reactivate the voice mail of the user account via powershell, even if the voice mail setting was already enabled.

The powershell command is
Set-CsOnlineVoicemailUserSettings -Identity sip:email address removed for privacy reasons -VoicemailEnabled $true