For the Enroll Customer API, I set the value of "userKey" parmeter as unique string of user(such as email or mp). And only one card is contained in the "cards" parmeter every call of API. When I call the API to bind other card for user, the response is that:
"errorMessage": "The UserKey provided is already in use."
So how to solve this problem?
Should I call the Unenroll Customer API first and then call the Enroll Customer API of containing all the user's card ? Or I can generate a different userKey every time call for the same user ?
A confuse, is the "userKey" parmeter related to user or user's card?
We are looking into the options which can resolve this for you. we will get back to you shortly.