There are three ways to access your voicemail using your phone's dial pad. You can: Press and hold 1. Dial *86. Dial your Xfinity Mobile phone number. NOTE: If it's your first time calling into voicemail, follow the recorded instructions to create a voicemail PIN. You’ll then record your name and set up a greeting.
In my (US-based) experience, doctor offices & the like have a place where you can fill out if they can leave messages or not (and some even have asked detailed messages vs callback messages), so that's my perspective! And that I can set different things for different numbers. So my cell phone they can leave detailed messages on any matter, my mother's house phone is detailed from billing only and otherwise callback, her cell phone is callback only. (And they also aren't allowed to tell her anything other than billing, so even if she does call them back about anything else! That was just a measure set up when I lived with her one summer & had no cell reception at her house.)

3. Enter your Pin Number. You will need to know your pin or passcode in order to check your voicemail. If you don't have this code, you will have to retrieve it from your carrier. You will hear instructions to input your pin. Hit the pound key after you enter your pin. Follow instructions on how to listen to your voicemail. It's usually to push a certain number (like 1). That's all there is to it. You should be able to hear your voicemail messages now.
In my (US-based) experience, doctor offices & the like have a place where you can fill out if they can leave messages or not (and some even have asked detailed messages vs callback messages), so that's my perspective! And that I can set different things for different numbers. So my cell phone they can leave detailed messages on any matter, my mother's house phone is detailed from billing only and otherwise callback, her cell phone is callback only. (And they also aren't allowed to tell her anything other than billing, so even if she does call them back about anything else! That was just a measure set up when I lived with her one summer & had no cell reception at her house.)