Rapid Ring - Cannot sign in

I am running an older version of the Rapid Ring app on an old (IOS10) iPAD. I had reason to re-install the app (electing to redownload and install the latest 'compatible' version. I have since been unable to log in to the app. I get a failure and a message saying cannot log me in at this time.The Full Ring app runs on the same iPad without any issues (apart from taking too long to load and so not being useful for dealing with notifications)I can log into Ring using the same credentials. I have deleted and re-installed the App and restarted the iPAD but the issue remains.Any help welcome! CheersJohn