FaceTime wants me to use teams or WhatsApp

I used to be able to FaceTime my mom all the time, she also has an iPhone. One time I accidentally clicked Teams to call her and now it won’t allow me to call her anymore on FaceTime and gives me this message:

Choose Another Phone

Number or Email Address to Call "mom"

"+1(xxx)xxx-xxxx" in the contact card is not available for FaceTime. (Number redacted for safety obviously)

I’ve deleted her number and her contact and re-added it. I’ve blocked her and unblocked her. She can make FaceTime calls on her end to her friends, has anyone had this problem and found the solution?