Thank you for contacting us. Are you able to open mSecure now and unlock the app on any of your devices, or are you completely locked out of mSecure on all them?
When a phone is reset or restored from a previous backup of the phone, the registered fingerprint or face data stored in iOS is reset. It is not carried over through the reset or restore. This is why after the process finishes, you have to re-register your biometric data in the device's settings.
Regarding mSecure, third party apps don't actually perform the fingerprint or facial recognition. They simply hand off the request for the user to authenticate with the device, then the OS prompts the user to lay their finger on the scanner or hold their face to the camera so facial recognition can be performed. Since the old biometric data has been reset, the secret keys mSecure needs to decrypt the information in the app are no longer available. This is the reason the app can't unlock using your fingerprint or facial recognition. In order to enable biometric unlock for mSecure, you would first need to manually enter your password to unlock the app. After mSecure is unlocked, it would be able to store the necessary security information with the OS which would make unlocking the app with your fingerprint or face recognition possible again.
I'm not sure how you would like to proceed, but please let me know, and I'll try to help in any way I can.