In-app purchases are directly managed by the Apple App Store or Google Play Store. If you have not yet added a card to the store, you need to add one before proceeding with the purchase. If you already have a registered card, the reason for the rejected transaction could be, for example, a lack of funds or outdated/incorrect card information. For more information, we recommend checking the status of your card directly from the store in the settings of your account under "Payment methods." Accepted payment methods vary depending on the device used and the selected payment type.
iPhone
Visit Apple Support for a list of accepted payment methods by the App Store.
Android
Visit Google Play Support for a list of accepted payment methods by the Google Play Store