SuiteTalk: error when adding customerpayment. Error ID: iappaxn515td1xx877mxm

I use webserivces to initialize and create a new customer payment. I got it to work when adding a new card as the payment method but when i want to use an existing credit card by assigning the internal id.. I get this error message:

An unexpected error occurred. Error ID: iappaxn515td1xx877mxm

what does the Error mean?


the code in red is not working!

var customer = (Customer)readResponse.record;

InitializeRef customerInitializeRef = new InitializeRef();
customerInitializeRef.type = InitializeRefType.customer;
customerInitializeRef.typeSpecified = true;
customerInitializeRef.internalId = customerInternalId;


InitializeRecord customerPaymentRecord1 = new InitializeRecord();
customerPaymentRecord1.type = InitializeType.customerPayment;
customerPaymentRecord1.reference = customerInitializeRef;


var read1 = _service.Initialize(customerPaymentRecord1);