Maybe a strange result of a particular set of circumstances, but...
I let an account that held a house close a few weeks before they announced 'Return', so played it again for a while in the 'free' period and transferred the house it had held on to a friend. After that transfer, I used that account to test if placing was possible somewhere else, and sure enough the account could place - but the house immediately went into the decay cycle.....
I'd suggest asking a friend to have a look at the house you placed just to make sure it's not done the same.