House owner not returning back the deposit amount

Hi, my name is Debashish. I entered into this new rented property in Mumbai in the month of June, 2017. I had made a rent agreement with the owner, for 24 months and had a lock in period mentioned as that of 12 months. It was agreed that in case I have to vacate my flat within the lock in period, 0.5% of the initial security deposit will be deducted. Now I got a new job in September and had to vacate the flat by November 15th. I informed the house owner immediately i.e in September itself. However, it's December now and I didn't get my security deposit back till date. Initially the owner stated that he will pay the deposit only after he gets the new tenant, but now even after almost 15 days have passed since the new tenant has moved in, I haven't got back my amount. The owner is clearly ignoring me and not picking up my call. The owner was particularly rude and misbehaved before also and I somehow had the notion that he might do something similar with the deposit amount. So, I handed over the house keys to my neighbor and informed the owner that he can take back the keys once he returns the deposit amount. However, he went to my neighbors' place and misbehaved with them as well. Somehow he got hold of a duplicate key and let the new tenants into the flat. Please suggest as in what I should do now.