Yes agree with Mr. Raja ji reply , IGST is applicable

Thanks Mr Raja and Mr Pankaj for the reply/support.When we are applying IGST and place of supply as Kolkata (since work has been done in Kolkata),Error is showing in Tally when generating GSTR3b. Please suggest.

According to Sec 8 (2) of IGST Act, subject to provisions of Sec 12,supply of services where location of the supplier and the place of supply of services are in the same state or U.T  it shall be treated as Intra-state supply except to S.E.Z.