Motorola One Action
Model: XT2013-4
Android 10, kernel 4.14.113-user+, build QSBS30.121-12-12-10
Verizon prepaid, 5GB/month
This phone with this service does not display voicemail notifications. Out of the box without any other apps, no notifications are displayed when a voicemail is waiting. In case it was the phone itself, I replaced it and then new unit has the same problem.
In an attempt to get around the problem, setting up third-party voicemail apps such as Google Voice result in the error "Call forwarding function is not allowed while roaming". This occurred with another app and also when setting up call forwarding by itself (for the sake of testing). Needless to say, I am not roaming when trying to use these apps and features.
The one thing not tested is whether using an annual plan rather than prepaid would enable the nonfunctioning apps/features. As you might guess, I am a very light data user. Tripling my monthly cost is not a reasonable solution.
(Previously posted as a reply to an identical problem here: https://community.verizon.com/t5/Android-General/Call-Forwarding-Not-Working-on-Moto-One-Action/m-p/1224979/highlight/true#M130304)