Companion app not able to login

Downloaded but cant login, entered email address and hit enter and nothing happens, deleted and downloaded again but no change, I don’t really want the app but I have ordered Zwift Play and believe I need the app to update firmware?!

Two F%$&ing hours in and I remembered 2 years ago I had a similar problem for the app that came with the Thinkrider smart trainer (returned as broke first ride), I made the font larger on my phone and in turn this affects what you see in apps, I could not see the bit to enter my password with the font enlarged.