Incorrect QR code, failed match payments

Unfortunately we have several problems with PayU plugin and their handling of issues. QR code for EUR order was generated incorretly and they were not able to match the payment to the transaction. They did not inform us and only after we kept chasing customer to pay and customer provided payment confirmation were we able to get PayU admit they received the money. They then decided to cancel the transaction as the QR code they generated was incorrect and the amount they received was not exact match to the transaction. Refund to the customer still has not been processed, damaging our brand reputation and causing us financial loss in lost revenue. There were other issues but this is the most recent. Definitely do not recommend. We cancelled our contract with them now.