I sent it to an apartment in my building which doesn't exist:
999 Nth St, Apt #999
versus
999 Nth St, Apt #123
It was sent to the former type of address, not the latter which is mine, in a building which only goes up to #555.
The really weird thing is that it had my name, the correct building, the correct city and zip, and the leasing office accepts all packages. WHERE DID IT GO? <_<