<h1>GST: invoice matching and system verified ITC failed; portal design and reconciliation gaps exposed revenue and operational risks.</h1> The report finds that while GST achieved structural tax unification and a single IT interface, the critical invoice matching and system verified Input Tax Credit mechanisms did not operate; GSTN portal modules were partially implemented and misaligned with statutory requirements and SRS, causing registration, payment reconciliation and IGST settlement errors, acceptance of improper ITC claims, and unresolved IGST balances; weak change management, testing and business continuity further aggravated operational risk and impeded centralised verification of transitional credits.