Regarding House Tax in Delhi

You can approach the bank, and take a copyof that cheque presented for collection and simply inform Corporation that the amount was paid through cheque on such and such date, through chenque No....dt ......for Rs.   of Bank ....................  Enclose a copy of the cheque.

 Please try to ascertain the validity of the demand.

Demand for taxes is the first charge on the property. The amount needs to be paid, if outstanding. You have a right to recover from the previous owner. The amount being  small, too much effort may not be worthwhile.

Whether your mother did not verify municipal records and insisted for receipts issued by MCD ?

How MCD can claim property tax of 15 years ? Approach Joint Assessor & Collector of your area MCD (North / South / East ).