Paypal Error 12001 UK Maestro 3D?

[theheel]

We have this error code for Maestro payments, which relates to early implementation of Maestro 3D security by Paypal.

Customer sees the error and tries to pay again (possibly with alternative card) , and we end up receiving funds twice & have to refund duplicates or they abandon their order and we have payment but no order detaisl.

Paypal forum says we should look for "ACK = SUCCESS" and now also for "ACK = SuccessWithWarning"

Any advice on where/how we can fix our code to correct this and stop duplicate payments would be greatly appreciated.

Thx