There is currently an issue where players may be unable to purchase crystals on iOS. This issue can be resolved by restarting Shadowverse.

If the issue persists, please contact the App Store. When contacting the App Store you may need to present your purchase receipt. Please make sure that your email address is set to receive purchase notifications.

Additionally, if you encounter an error when trying to purchase crystals, it may take some time for the purchase to be reflected into your account. Please wait a while and then try confirming your crystal balance again.

Shadowverse Team