how to update payment details

Change or remove your payment information from your iTunes Store account (Apple ID) - https://support.apple.com/HT201266 - "On your iPhone, iPad, or iPod touch, you can change the payment information for your Apple ID in Settings. On your Mac or PC, you can change your payment information from the iTunes Store." - More information at: https://discussions.apple.com/thread/3251676?answerId=15891166022#15891166022 and another tip at https://discussions.apple.com/thread/8010960?answerId=32902784022#32902784022