This worked for me:
Go to the app store, uninstall if possible. It may not do that, but might downgrade the app initially.
If it gives the option to "update" choose that.
App started working again.
Try not logging in with your user/pass instead tap on "not the account holder, continue with mobile number." and enter your mobile number you should get a confirmation code to enter and you should be able to see your account. Sometimes when doing that it takes you directly to the screen to enter the code and not the phone number just hit back and you should be able to get to the screen to enter the mobile number.
Good morning @BarryBonz , did you try restarting your phone? That happens to me on occasion and I either close the app and clear the cache,or restart my phone. Works 99% of the time. If it persists, call tech support from your device at *611 and get assistance troubleshooting. Hope this works for you