If you want to change the billing details for phone subscription it can be done from the phone settings.
Follow the following steps:
Step 1: From the phone setting, select the Credit Balances tab.
Step 2: Select the number for which you would like to change the billing details.
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Step 3: Select the Billing details option at the right end of the number.
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Or , you can select the credit balance setting on the top right corner.
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Step 4: Make the necessary changes you want to make and then select the save changes option.
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