We are taking care of my mother in our home and a person calls her who incites her to think and believe things that aren't true. It looks like this caller wants to get control of her for financial gain but we've been told that until my mother is willing to admit this person is dishonest, or until the caller overtly breaks the law, there's nothing we can do about it. My mother would be upset if we told her she couldn't talk to the caller because she says the caller is her friend. The caller calls from different phones so we really can't block the calls anyway, even if my mother agreed to it.
From your landline you dial *72 and a prompt will tell you to put in your forwarding number. To reverse this you dial *73.
While I don't personally know my mother's friends, I do hear all about their lives and their dramas. Do you not even know who this person is? This is elder abuse and should be treated as such.
Yeah, mom will be mad when you cut the cord, so to speak, but she can't protect herself, so you'll need to.
Hopefully, you have POA. As such you are Moms representative and responsible for her finances and health. I will assume here she suffers from a Dementia maybe in early stages. Even so, you need to protect her. Even in early stages, reasoning goes out the door.
If Mom has a cell phone, there should be a feature that only those on her contact list can ring thru. The ones that don't go to VMail. You can then see the number used and block it then delete the VM.
Landline, get Caller ID. If the name or number is not familiar allow to go to VM. Try to get Mom to understand not to pick up the phone.
Mom lives with you. Hopefully if he/she calls on your the landline you pick up first. Let your husband do it. Tell the person that they are not to call again. Maybe tell a fib and say the phone is wired.
I know you realize this is a scammer since they call from different numbers. You may want to tell them that you are now in charge of Moms finances so they are beating a dead horse. Bet they don't call again.