Inter State supply reporting: ensure place of supply accuracy and correct ITC reversals in GSTR returns to secure proper credit allocation. Registered persons must report inter State supplies place of supply wise in GSTR 3B table 3.2 and corresponding GSTR 1 tables, maintaining correct customer state data; GSTR 3B table 4(A) is auto populated from GSTR 2B but reversals and ineligible ITC must be identified and reported so only net eligible ITC (4A minus 4B(1) and 4B(2)) is credited to the electronic credit ledger. Absolute non reclaimable reversals go in 4(B)(1); conditional reversals that may be reclaimed go in 4(B)(2); time limit based ineligible credits are reported in 4(D)(2).