Cannot join football centre

I cannot complete Day 4 “Join Football Centre”.

Tapping the button shows the Football Centre flaming ball icon, screen flashes black, then returns.

This occurs on multiple devices (iPad and iPhone)

I have:

1. Restarted the ipad
2. offloaded & reinstalled the app (closest thing to clearing cache on iOS)
3. tried a different device

all result in the same thing