Castle recycle won't unlock after doing all I was supposed to to open it

[Indys2nd]

I can't tell from your post where you exactly started to have a problem with this quest line. So here is a link to the clash of clones wiki that might help you out:  http://simpsonswiki.com/wiki/The_Simpsons:_Tapped_Out_Clash_of_Clones_content_update .

If you haven't completed one part, you can't go onto the next. Feel free to post again if this doesn't help and be specific as to what is happening with your game (last task you finished.)

For others reading this post, the wiki is kind of a spoiler, so don't click the link if you don't want to know the quest line. 

[dontknowathing]

I had this problem too. It isn't made clear that you need to do A in order to do B so you can do C. basically, you have to upgrade the Eco castle to level 6, which is when the recycled towers are unlocked and two of them are placed in the inventory, then Lisa can do her quest.