Assistive Touch issue with Apple Pay on iPhone 16 Pro Max

I had an iPhone SE 2020 for four years and never had a problem with Apple Pay. I just bought an iPhone 16 PM and Apple Pay was working just fine. Then one day out of the blue when I double tapped to pay, I got a notification that stated, “AssistiveTouch is turned off. To confirm with Face ID, turn on AssistiveTouch in settings.”

Going through these steps never resolves anything. It’s confusing and sends me down a useless rabbit hole. How do I go back to using Apple Pay and getting rid of this horrible alert?

Thanks!

[Re-Titled by Moderator]