Just signed contract Leaking Roof in Co-op

Our contract was executed and our escrow deposited, When we got the contractback our attorney mentioned a letter that from the board that stated the roof has leak (the apt is on the top floor) and that the leak will be fixed. I contacted the broker asking when it will be fixed since even though we need to do renovations it's better to not have leak at the same time. It's taking time to get an answer, but shouln't this have been done before the apt went on the market? are they acting in good faith? since the contract is signed did we lose all leverage? Really all I want is it to be fixed before we move, but I have a feeling boards will take time to get it done. Any help appreciated thanks!