Calls on Assistive Access not working

I recently got a new iPhone for my mom so that she could have Assistive Access due to her declining cognitive health. I selected the family members she calls the most as her favorites, but when attempting to call some of said family members (myself included), nothing happens. It works for about half the contacts, and not for the other half. I’m her main caregiver so it’s pretty ironic that I’m one of the ones it doesn’t work with. I’ve tried exiting and re-entering Assistive Access, deleting and re-adding all the contacts, restarting the phone, force-restarting the phone, and checking if the iOS is the most recent update (it is). Nothing works. Please help.