That's rather odd. From your post it seems the update you've made a few months back caused this. Do you have the latest version of the app now installed though?
Also, are you logging in unto the app with your phone number instead of your email?
Please keep the Community posted and we'll reassess accordingly.
The first thing that comes to mind when reading your post is that you maybe need to update your device.
If you've got the latest version of the Fido My Account app but your software is not up-to-date, that can create a conflict in the execution of the app.
Try that before anything else and let us know how it goes!