Yellow floor tiles?!?

[jumpinheather]

I've completed the challenges an awarded an animated monster. But all that appears is a yellow floor square. They go away if I shut down & log off but still can't get them.
What to do next?

[kooky panda]

I've completed the challenges an awarded an animated monster. But all that appears is a yellow floor square. They go away if I shut down & log off but still can't get them.
What to do next?

Try storing it and taking it back out. Also try restarting your game or device.