HelloWorld Technologies India Pvt Ltd - Security deposit of 9000 not refunded by the firm

I had been a resident of HelloWorld kohinoor Hyderabad since February for which they kept security deposit of ₹**** which is refundable after we vacate PG as per compaby rules. I as per rules, submitted one month prior notice after paying full month rent. As per company rules I am supposed to get my security deposit amount of ₹****. I vacated the PG on **th July, **** , however I paid my room rent upto *rd of August, ****. After *rd of August I was due for my security refund of ₹**** which the firm is now refusing to pay. It is now two months and they are not refunding my money.
I have mailed them many times, contacted them on customer care but they are unethically trying to harass me by not refunding and replying. After multiple mails, out of **** rupees, they sent me **** rupees only. I was a student gone for internship and this is my hard earned money. Kindly help me by refunding my entire money from Helloworld.
I asked them to provide me the balance sheet that shows how much and why the amount was deducted. I was shocked to see that they deducted electricity and water bills which according to their company rules are included in monthly rent. They also deducted joining fees of approx ₹*** which was not even mentioned in their rules at the time when I entered this firm. Even their electrity meters were installed around the time when I was going to leave the PG. They forcibly deducted all these utility charges. Even some of my friends who stayed there are facing same issue.