Answer
First verify with all members of your household that one has not been received. These come in a white envelope that has the Parking Services address as the return address and will be mark with "ATTENTION: DECAL ENCLOSED."
It is the responsibility of the purchaser that is the decal has not been received in the mail within 3 weeks of the shipment notification, to come get replacement decal. The fee will be waived. The Request for Replacement Decal must be turned into Parking Services in Harper 1090.