I get the message "Your sim is currently in the unit" when there are no sims on the lot.
Ideas
Status changed:
New
to Declined
You have already posted here: https://answers.ea.com/t5/Game-Issues/quot-Your-sim-is-currently-in-this-lot-quot-when-there-is-no-sim/m-p/14175939
Please post more info there.