go to settings> iTunes and app store tap on your apple id then choose view apple id put in your apple id password then choose payment method and change your payment method
The balance isn't in your phone, it is stored on one of Apple's computers and any device using your Apple ID will show it. Log into your Apple ID on the other phone.
Sign in with a different Apple ID on your iPhone, iPad, or iPod touch - https://support.apple.com/HT203983 - Change iTunes Store account on an iOS device - Log out of your current account with Settings.app > Store (Settings > iTunes & App Stores on iOS 6) > tap on your AppleID. Log in with a different account. Note, turning on automatic downloads or re-download past purchases may tie the device to that account for 90 days (View and remove associated devices in iTunes - https://support.apple.com/HT204074)
How can I remove redeem gift card out of my phone?
