Who I have the same questioned this topic

I'm trying to activate advanced calling on my s7 with Android 7.0. I have HDVoice on my account.When I go to Settings/Advanced Calling the Activate Advanced Calling is grayed out. In Advanced Calling I turned on HD Voice & Video Calling. In Wi-fi Calling I turned it to On and set my emergency address bu Still Activate Advanced Calling is gray.

I have wifi speeds in my house of 115.88 down and 3.22 upload so I don't think that's the issue.

Any suggestions on getting this to work?

thanks,

Clare