iPhone SE 2022

OK, I have a new iPhone SE 2022 and I can't receive any voicemails... My old iPhoneX phone worked with the voicemail feature fine with MintMobile. I can hold #1 down on my keypad and get the voicemail prompts, but none of my four children can leave me a voicemail. They state that my phone rings and rings (and I hear and see them calling), but after about 10 rings, they are simply disconnected and not given an opportunity to leave a voicemail... I cant find any help on MintMobile's website...