Since there is no VAT involved, you can opt to disclose this in the current VAT return and no VD would be required. Haven't you submitted a refund claim till now? If yes, it is likely that FTA would have queried this already.

Hi Vaishali, I agree with the view of Sajith that the same can be corrected in the current VAT return. However, kindly note that you may still be liable to administrative penalties under Cabinet Decisions No. (39) and (40) for 2017 on Federal Tax Authority's Service Fees, Administrative Fines for "Incorrect Submission of Tax Return by the Registrant".