I am using CIM for payments and i am doing testing by using test credit cards provided at authorize.net website, i used 4012888818888 for my first transaction and it worked fine.
Then i changed it to 4012888815555, 4012888814545, 4012888814444, 4012888816666 and it resulted in error and i got a message "The credit card number is invalid".
After that i changed the credit card number to 4012888815454 and it worked fine. This credit card is not there is list of test credit cards and i am not able to find it anywhere. I am not sure if there is any issue in my coding or if there are some permutation and combination that may also work, either they are not in list!!.
Please let me know in case i am doing something wrong.