Can't check in on Delta flight to New Zealand

I am leaving for New Zealand tomorrow from the US (where I am a citizen) and Delta is not letting me check in on the app or online/desktop because it says I don't have an NZETA which is required to travel to New Zealand. I do have an approved NZETA and so does my husband. I can't figure out why he was able to check in and I am not but I triple checked the passport number and everything and all of the information is correct in both places so I can't figure out why it won't let me check in. Please help!!