Previous owner at fault

The previous owner has the resposibility to release all sale properties to the buyer.
If the security is included in the sale, the previous owner shall release the security box key.
If the security is not include in the sale, the previous owner shall remove the security box before sale closure.

Anyway, you need to negotiate with the previous owner for such a small amount of money, or you can choose to sue for damage compensation if the damage is big.