I'm attempting to complete a lvl 35 Main story mission quest but when I speak to the NPC nothing happens.

The quest I'm trying to start is the one that follows;
With a little elbow grease and You can't take it with you.

I have finished the quest and proceeded to 11-21 to speak with the NPC to start the next quest and nothing happens. I tried logging in and out, restarting PC a different PC and nothing works. While I was there, someone else was also having the same problem.

Some one please help me out.. I'm stuck.