The details of the TCS collected would be reflected in the seller’s GST portal.
For verifying the TCS credit at your GST portal:
Login –> Select month
–> Click on “TDS and TCS credit received”
–> Click on ‘TCS credit received’
–> Select GSTIN wise TCS details and accept
–> Accept the declaration and proceed to file
–> File TCS credit received summary
–> Check for balance in electronic cash ledger