Main Gate Security Chain Installation Update & Bathroom Exhaust Fan Issue

The security chain for the main gate has been installed, thank you for your arrangement. However, due to the new chain being too small to cover the opening left by the old one, the original screw holes of the old lock can still be seen. Attached is a photo for record.

Additionally, the electrician who came to inspect the bathroom exhaust fan last time pointed out that there is actually a part missing from the fan. How should we handle this? We are worried that without the fan, moisture will accumulate and worsen the existing mold problem on the walls and bathtub.

The kitchen sink faucet has also become loose during normal use. Could someone take a look at it when they come to pick up the items?