IOS
After finishing the 5 initial training duels where you get the starting cards I am unable to log in the game anymore (tried several times for 2 days. The game starts to load but then just gives some network error althought when I try the option to check status all seems correct.
PC - Windows
I tried playing through Steam on my PC running Windows as well. I dowloaded the MTG Arena, signed in with the same credentials and got the exact same problem. So, the issue is not related to the platform