You're using an older iPad? Yeah. Go
here and add your complaint to the list. The more people who complain the faster they'll get to it.
You might also contact Customer Support and open a complaint ticket.
Unfortunately, they probably won't fix it until the next Event update. That's usually how they handle these things.
This is ridiculous though. My iPad Mini 2 may be a little out of date but it's the best/fastest/most reliable device I own to play this game on.
I will mention that there IS a way to play this game on a computer, but discussion of that is not allowed here so you'll have to research it yourself.