The Internet keeps me from dreaming
In Animal Crossing: New Leaf's Dream Suite, Luna keeps telling me that I can't dream because of an unstable internet connection. I am connected to the Internet on my 3DSXL and can use other networked games and apps just fine. I can download items from the post office just fine as well. I don't have anyone on my friend list whom I can pay a visit to over the internet, so I can't test that. My network data is also up to date as well.
What are the network requirements for Animal Crossing: New Leaf?
Solution 1:
I ran into this earlier yesterday. Animal Crossing: New Leaf's automatic dream-matching can sometimes find 0 matches (verified by choosing "I'll search for one!" and then asking for a list of dreams from Luna, which should result in an empty list), and thus the game automatically assumes your internet connection is unstable because of this.
It's likely that the dream-matching is location based and there are likely no uploaded dreams nearby.
To avoid this, you have to search for an available dream via dream address, player name, town name, or list by country. It seems to be an oversight from the developers, here.
Solution 2:
The real issue is a lack of players sharing their towns at the time. Nintendo has since put a town of it's own online for players to explore, ensuring at least 1 possible "dream".