1. First, you can directly call the customer service phone of the credit card issuer to apply for cancellation of the secondary card, and follow the voice prompts.

2. Secondly, if you go to the business outlet of the credit card issuing bank, you can also cancel the supplementary card of the credit card, and you can follow the tips of the branch staff.

3. Finally, log in to the mobile banking APP or online banking of the issuing bank and find the option to cancel the credit card. You can also cancel the supplementary card.