I want to buy more iCloud storage, but every time I add my mastercard (Debit card), I get above error message. My card is registered on my name & address. Every card detail is correct. Any alternative to buy more storage?
See the Apple Support article(s) below.
Possible fixes. Fix ‘Your Payment Method Was Declined’ Error In App Store
Payment method declined in iTunes or the App Store ...
If necessary, contact iTunes Support for assistance. See the Apple Support articles below for contact information.
Apple Support schedule phone call
If necessary, try Twitter
https://twitter.com/AppleSupport. People have posted it may take an hour or more to get a response.
iCloud Payment Declined. Add another payment method
