I believe USAePay requires the encrypted data to be:
- Encrypted with their public key
- Formatted in a specific manner
- Passed in magstripe or credit card number field
Because you are using their PaySaber hardware, see below for step 3.
USAePay Wiki - End To End Encryption:
If you are using idynamo library, here is what you need to do:
NSString *responseString = [mtSCRALib getResponseData];
NSData *responseData = [responseString dataUsingEncoding:NSASCIIStringEncoding];
NSString *encodedString = [NSString stringWithFormat:@"enc://%@", [^] [responseData base64Encoding]];
and then send encodedString to the gateway as MagStripe.