The details of supplies and the amount collected during a calendar month which is furnished by every operator in his return will be matched with the corresponding details of outward supplies furnished by the concerned supplier in his valid return filed under section 37 for the same calendar month or any preceding calendar month. Where the details of outward supply, on which the tax has been collected, as declared by the operator in his statement do not match with the corresponding details declared by the supplier the discrepancy will be communicated to both persons.
(ICAI FAQ PUBLICATIONS 06-09-2017 TAX PAYMENTS, INTEREST, PENALTIES AND OTHER AMOUNTS: FAQ NO. 61)