Quest not working properly (The Missing Mechanical Parts)

Where did you find and/or notice this bug?
Ludibrium: Toy Factory <Process 1> Zone 1. (Where the NPC called Assistant Chen is located)

Can you describe the bug in detail? If not, can you provide a screenshot/video of the bug?
After talking to Assistant Cheng and accepting the quest called "The Missing Mechanical Parts", you have to talk to Assistant Cheng again to do a jump quest in another map, but when you talk to him again and click to teleport to the other map, this massage shows up: "Sorry, but the Toy Facory is currently unavailable". Which makes the quest impossible to complete. (See screenshots in attachments)

What is supposed to happen?
You are supposed to be sent to another map to do a jump quest.

Can you provide a step-by-step guide to re-producing this bug? (Please be as specific as possible.)
- Get to lvl 30
- Head to "Ludibrium: Toy Factory <Process 1> Zone 1."
- Talk to Assistant Cheng and accept the quest called "The Missing Mechanical Parts".
- Talk to Assistant Cheng again
- Click on: "The Missing Mechanical Parts: Toy Factory <Sector 4>" (This should take you to the map, but doesn't)
(see screenshots)

 

That quest is currently closed because it was abused by others to gain unfair advantages.

 

That quest has been temporally disabled due to a possible exploit (see link below). Your effort to make a well detailed report like this is highly appreciated though !

http://forum.maplelegends.com/index.php?threads/quest-the-missing-mechanical-parts.3418/