Brokerage Charges

I rented an apartment last year. I consider the person showing me apartments as the broker. Once my wife and I decided on one, our broker introduced us to a firm that said they handle the properties of the apartment owner, since he resides in Dubai. We signed the rental agreements between the landlord and us (the tenants). We paid our broker one month's rent as brokerage charges. Now that we need to renew the rental agreement, the firm handling the property called us and said that we need to sign the new rental agreement, and also pay them a brokerage fees of Rs. 5,000. Are they right in asking for brokerage fees for renewal of rental agreements? No where in the agreement it is mentioned that they are our brokers, nor was it communicated verbally. We were always dealing with the owner. I have told the firm that they have been always behaving like property managers for the owner who is not in the country. That they have never verbally or in mails and in the agreement communicated to us that they are the brokers. Is what they are doing right?