Currently, in-game products can be purchased through App Store and Google Play Store. 

Due to differences in payment methods, we ask for your kind understanding that immediate assistance may be difficult.   

■ For the payments that were declined or rejected:  

1. Force close the game and reenter in a stable network environment  

2. Check and troubleshoot the account & payment info on the CS Pages of Stores.  

- Play Store (AOS) Customer Center: https://support.google.com/googleplay/?hl=en#topic=3364264  

- App Store (IOS) Customer Center https://expresslane.apple.com/GetproductgroupList.action 

Also, this might be related to your carrier. Check payment limits & methods and consult with your carrier's customer service. 

If the above methods do not resolve the issue, please click the [≡] Menu icon in the upper right corner of the game screen → tap the [⚙] Settings, and then send your inquiry through the [Support Center]! 

We will see what we can do.