iOS 2FA Edit Settings Continually Prompt When Password Changed

I've seen this same behavior in two separate customer tenants. What appears to be happening is if the Authenticator Mobile App had *any* previous registration, then after a password change, the broker relationship is lost (Authenticator App is used as a Broker to register the device into Azure AD for conditional access purposes) and so I believe the prompting is caused by conditional access not being satisfied with device claim being met. You can work-around this issue by modifying conditional access to not look for a particular device type (iOS/android) but I feel like this is a bug and I recommend you open a support case with Microsoft.