Strange text message shows while on a phone call with a family member

Has my wife’s phone been hacked?

In the past week when my wife is on a phone call with our daughter, my wife will see strange text messages show in the Messages app that looks like she is sending a text to my daughter but she isn’t texting. Some are words and some are symbols. It also seems like it happens at the same time (7:15 - 7:20 pm). After the second time, they did a test call tonight and it happened again.

My wife’s phone is an XR running iOS 14.2. No new apps have been installed. She changed her Apple ID password and we also changed our WiFi password just in case.