How do you access Live voice mail messages from a different phone? With My carrier VM, I press *, but it doesn't work if the message went to live voicemail.

When my iPhone 14 is on and live voicemail is turned on, if someone leaves a message, I am unable to retrieve it from another phone. With my carrier voicemail, if someone leaves a message, I can call my number from a different phone and press * during the greeting to listen to my voicemails. How do you retrieve messages left at live voicemail? My friend's iPhone 12 crashed and he is trying to retrieve his voicemails (same carrier) but can't . Said he had live voicemail turned on.