Input tax credit reconciliation requires payment or explanation of excess credit after electronic intimation, or statutory demand follows. An electronic intimation via Part A of FORM GST DRC 01C notifies registered persons where input tax credit availed in FORM GSTR 3B exceeds credit in the auto generated FORM GSTR 2B; the registrant must, within seven days, either pay the excess with interest through FORM GST DRC 03 or explain the difference on the common portal and record payment or reasons in Part B of FORM GST DRC 01C, failing which the unpaid amount is liable to be demanded under statutory assessment and recovery provisions.