Input tax credit mismatch monitoring requires timely Section 73 action and mandatory entry of follow-up details. Input tax credit mismatches between FORM GSTR-3B and GSTR-2A were identified in the GST MIS Red Flag Module for 2017-18 and 2018-19. Field officers are directed to complete proceedings under Section 73 within the prescribed limitation period and to mandatorily record the details of action taken in the departmental Entry Module for effective monitoring.