stanza living dijon house - security refund not processed

I have joined in a PG called stanza living dijon and I made an agreement for the tenure of NOV **** to ** JULY ****.and paid a security deposit of rs **** recently we renewed to stay for another year by paying **** but as the services are bad we decided to vacate and not to stay for another tenure i.e AUG **** to JULY ****. and I make it clear I renewed the service and I did not sign any second agreement . but now they say that the security deposit of rs **** will not be refunded as we renewed and it will be carry forwarded to the agreement of next tenure. but as we just reserved the bed but did not sign the agreement for next tenure. and when we ask for security deposit they are refusing to do it