Question about House Rental-Security Deposit

Hello, We rented an apartment 3 months back The agreement is for a period of 11 months. Although the following points are not a part of the agreement- 1.Notice period 2.Minimum lock in period Now due to maintenance issues in the flat,we wish to vacate as the landlord is not being able to fix the problems in the apartment. The problem we are facing is that the landlord says since we are leaving before the said agreement period comes to an end we have to bear the maintenance cost for the entire year as well as the brokerage HE has paid from his end to the broker,which is not mentioned anywhere in the agreement. We also were forced to pay a brokerage where the person who showed us this place had kept the fact that there was a brokerage involved as we got in touch with him on a website especially for non-brokerage transactions.This was only informed to us once we signed the agreement and we're bulldozed into paying. Would like some help as to how we can go about it now. Thanks alot