Buildings auto clearing? turn on your X-MAS lights to let your neighbors know...

I can log in with dollar signs floating over buildings. I visit Krustyville or neighbors and those have all been cleared with maybe some new ones showing collectible status. This has been happening since the end of the monorail event on both IOS 8.4 and 9. I tried the live chat but after the welcome to it I got no further response. It's impossible to collect if you're hoping to leave something for neighbors. It seems to happen to every building I have.