Refund of excess VAT: claims in prescribed form may be sanctioned, withheld, or made subject to security and interest. A claim for refund of tax, penalty or interest paid in excess must be made in Form DVAT-21 with full grounds and not duplicate a return claim; the Commissioner may require security in Form DVAT-21A and a certified court order must be attached where refund arises from judgment. If admissible, the Commissioner will determine the amount, sanction refund in Form DVAT-22 with calculations and interest, and effect payment by cheque or electronic transfer. Refunds are barred where returns are not filed, dues unpaid, or a withholding order operates, and the authority must satisfy registration-related conditions before allowing a dealer's refund.