If the Emirates ID is not collected from the post office within 90 days of notification, it is returned to the Federal Authority for Identity and Citizenship (FAIC). Once returned, you cannot retrieve the ID from the designated post office, and you may need to reapply for issuance. The notification SMS includes the location, date, and time for collection. Timely collection ensures smooth access to the ID, avoiding additional administrative steps or delays in obtaining your Emirates ID.