It depends on the terms and conditions of the tenancy agreement entered into between you and the Landlord. In usual circumstances, the Landlord will be responsible for the structural repairs of the premises. You should ask the Landlord to repair if the lease states that the Landlord will be responsible for that. However, the Landlord may argue that the lock does not work due to your negligence or fair wear and tear of usage.
In any event, the obligation to pay rent is en entirely separate issue and even though it is often done you have no doubt agreed not to deduct rent or refuse to pay rental because of the above matter.
Weir & Associates
Solicitors & Notaries
16th Floor Tak Shing House
Theatre Lane
20 Des Voeux Road Central
Central
Hong Kong
Tel : j2526-1767
Fax : 2868-3568
email :
weirlaw@hongkonglaw.com
www.HongKongLaw.com/weirlaw