Pre-import condition enforcement: affected importers must pay IGST and may claim refund or input credit via prescribed procedure. Mandatory enforcement of the pre-import condition in the Advance Authorization scheme requires imports failing that condition to be charged IGST and compensation cess with interest. Affected importers may apply to the jurisdictional assessment group at the port of import with documentary evidence to pay the tax, seek refund or claim input tax credit; customs will cancel OOC, reassess the bill of entry, accept payment via electronic challan, and make a notional OOC to transmit payment data to GSTN. ITC availability and refunds remain subject to statutory eligibility and rules.