You just have to pull it hard to open the catch inside is held in
by a couple of black plastic bits & when one or both of them break the lock goes out of line therefore all you can do is yank it open then you can take the screws out from the inside take the front panel off then you can get to the lock to release it then depending on how bad its broken you either need a new front panel or if its not too bad you can insert a small self tapping screw from the outside in one the 2 small holes to hold it in place
Colin, December 2005