Paid 6 months rent upfront and want to leave early

I paid rent in advance with a 6 month contract but want to leave just after two months. The problem is amounts of rubbish in communal areas, noisy and conflict marginalised neighbors, something is always breaking in the house - shower, socket, light, battery... And everytime you have to wait a week until the agency contacts the landlord and the landlord comes to fix it. In the contract, there is only a short line about early cancellation of the agreement, which warns of compensation for losses to the landlord if I leave earlier. The thing is, I don't mind finding a replacement tenant, but my estate agency is ignoring my questions about early cancellation of the contract. I’m thinking of coming and talking to them face to face, or asking the landlord directly. It just seems to me that they won’t want to return the money I prepaid in advance. What are my rights? What can I do? Living here makes me depressed