1. Check the In-App purchases settings:
- Go to the device's Settings app > General > Restrictions
- Switch In-App purchases ON
2. Confirm your Apple ID in the device's Settings:
- Close the game
- Log out of the App Store (device's Settings app > iTunes & AppStore)
- Start the game and try to make a purchase
- Enter your Apple ID profile data in the window that appears
- Confirm your purchase
3. Try different Apple IDs to proceed with payment.
Tried all of the above steps and still cannot make a payment? Please contact us at https://plrm.me/arena_support. We'll do our best to help you.