Duplicate Can't get warped to the quest map of "Shawn's Fear" for the skillbook of assassinate

When I was trying to complete the skillbook quest of Assassinate, this happened: I clicked Shawn for further quests but nothing happened and I didn't get warped to the map where I can collect the quest item. What's more, i can't get warped again since Shawn keeps telling me that I've already got in that map before. Please help me to get to that map so I can get the skillbook.

 

And I'm wondering will it work if I forfeit the quest restart it? IGN: Prof_Don

 

Not being able to get into the map is not something that has been a problem before so I doubt it would just happen now.

I am confused since you start with saying that you didn't get warped in and then you say you can't get warped again.
The portal is right there did you try walk through it?

 

Thank you Andreas, I changed channel today and it works. I guess it was due to network lagging or something. Anyway, thanks a lot

 

Glad it works, it's not uncommon for weird things to happen!