This issue only happens when I get a "Hard Level Offer" - not on all hard levels, just with the offer part. I am able to purchase other offers just fine as well as buy the offers I get for collecting scrolls or purchase bonuses or other things. If you look at the screenshot in the first message you can see what it looks…
I amusing the app on my iPhone 12 Pro Max. I can not clear the cache on it and yes I have tried signing out and restarting my device. That did not work.