MIL is confusing phone calls with actual visitors. Anyone else with this experience?

MIL has mild/moderate dementia. She lives in a small care home/adult family home.

Now she thinks phone calls are real people sitting in the same room with her. When ending a call she says thank you for coming, are you leaving from the front door or the side door?

MIL has left lengthy voice mail messages for DH many times a day and then started to freak out and called other family members to ask for help because her son doesn’t talk, he looks grouchy. He must be sick! DH changed his voice mail greeting from his own recording to a generic business female voice and that has helped with the freak out situation.

She had hallucinations/confusion thinking pictures are real people, that stressed her out because these people didn’t talk to her and she thought they need to go to the doctors. We took all the pictures away.

Now she has hallucinations/confusion between the phone call and real visitor.

Btw these are just phone calls not FaceTime or zoom.

Anyone with similar experience? Any med that helps?