I have the same problem and can't figure out what to do. I've actually noticed that some of my neighbours were able to expand the extreme borders (the incomplete squares) of their zoos but I can't. I tried buying expansions with notes and then coins but it made no difference.
Also the items I get from my tropical safaris aren't counting towards my goals. Is yours the same?
Yes - I have the same problem. I can only collect coins from my animals and hearts by visiting neighbors. I contacted support several weeks ago about the problem. (Go to sttings and scroll down to the bottom there is an email address for support - [email protected]) They say they are working on it - but appatrently not very quickly. The only way I can add new animals from the next levels at this point is to sell land embellishments that i previously purchased from the store for my habitats and consolodate my animals. This creates room for a few new animals. It's a catch 22 though because those embellishments increased the money I earned and without them, my animals earn less. Meanwhile by not adding animals, my zoo rating dropped from an A+ to a C. That's why I sold items to add new species. I hope they get the expansion problem fixed soon. The game has become pretty boring. Hope this helps.Is anyone else having a problem where you reach a certain limit and you can't expand anymore? That's what happened to me - I want to keep playing but I'm out of room! Does anyone know how to fix that??