Can you please check that:
1. You have removed the magnetic key from its base holder. Twist the cap to remove it. The keys do still open doors in the holder but the magnetic reach is greater if removed.
2. The hook moves back and forth when you press the magnetic key against a lock on an opened door. Ensure that the lock is set to open mode.
If the above is OK, put the magnet against the door, and gently push the door to give the hook a bit more clearance space to move. The lock may be installed too far away from the catch.
Should you need any further assistance, please contact our friendly customer care team!