Electronic Cash Ledger integration requires payment with interest and application for interest refund after Out of Charge regularisation. Users whose duty payments failed to integrate due to ECL glitches must select unpaid challans, pay duty including interest within the prescribed window from the date of removal of system inability, and, after integration and marking of the Bill(s) of Entry as Out of Charge by Customs, may apply to the relevant formation for refund of paid interest under the Waiver of Interest order; reporting of absent unpaid challans or implementation difficulties must be made to DG Systems or ICEGATE HelpDesk with screenshots.