I gave a loan against property in Kolkata and the borrower is not repaying what to do

If the loan was secured by a mortgage of property in Kolkata, you can file a suit for mortgage before the civil court seeking sale of the mortgaged property for recovery of the loan. Under the Transfer of Property Act and West Bengal Premises Tenancy Act 1997, a mortgagee can approach the court in West Bengal for a decree for sale of the property. You must produce the mortgage deed, loan agreement, and default notice as evidence. You can also file a suit for recovery of the loan amount as a personal debt. If the borrower is untraceable, you can approach the Calcutta High Court under West Bengal Premises Tenancy Act 1997 for permission to proceed ex parte.