Just log in to the ICBC website, enter the bank card you have opened for online banking, click "My Account" and your card information will pop up, then click the "Account Management" drop-down menu on the left and there will be "Add" Account", just add your credit card information.

Note: The two cards must have the same name. For your question, I went up specifically and added my own card again. I hope you are satisfied with my answer.