We fly Southwest. you can complete the form beforehand by contacting your airline
Southwest makes you file the form ANNUALLY. i am guessing the document date is for the form. You just need to call and get a new form for the year 2024.
its not that they wont accept your service animal, but that the airline form needs to be filked out annually.
call your customer support line at your airlines. we submit our form at the check in counter for the flight, when you get your boarding passes. when you fly with animals, you need to check in manually. they tag the carriers and give you a pass for your animal too.
hope this helps