Input tax credit discrepancy triggers electronic notice and mandates rectification or addition to recipient's output tax liability. Discrepancies from matching inward and outward supply details are communicated electronically to supplier and recipient via designated portal forms, enabling each to rectify outward or inward statements for the month in which the discrepancy is communicated. If unrectified, the unreconciled amount is added to the recipient's output tax liability in the return for the month following communication. Rectification by supplier means adding or correcting outward-supply details to match recipient declarations; rectification by recipient means deleting or correcting inward-supply details to match supplier declarations.