@Shawn ********
you can file a 90 day report in person 15 days before down until 7 days AFTER it's due with no fine. Even if you miss the window to file, I'd just wait until you're back and file one late in Chiang Mai, take the 2000baht failure to file penalty and chalk it up to experience.
OR
Try the online portal and see if you can get it to go thru using the chiang mai address that you used when you got the extension and where your TM30 was filed.
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