Transfer visual voicemail from Iphone 8 to Iphone 12

I performed a data transfer to the new phone and all data transferred EXCEPT for voicemail. Have tried a few third party transfer applications, no luck. After mining online have also tried airdropping the messages, transferring via various cloud storage services, email, text, etc. In all cases it transfers just the audio file with none of the info tag (date, time, phone number), and not into the voicemail part of the phone app. Voicemail is empty with msg that says "Call Voicemail". Phone call with carrier (T-Mobile) also fruitless.

Any ideas?