Just FYI, I went to Chiang Mai IO for my 1 year extension of stay based on Thai spouse but didn't have a print out of my TM30 as I've always used the Section 38 app. and unfortunately when I did it in January, I didn't screenshot it and of course when I went to pull it up, screenshot and print it later, the system was down. I was expecting a fine but I just explained what happened and they gave me a new TM30 receipt, no charge. Everything else was fine.
TLDR : Answer Summary
A user shared their experience at the Chiang Mai Immigration Office while applying for a one-year extension based on their Thai spouse. They encountered an issue as they did not have a printout of their TM30, having used the Section 38 app and not captured a screenshot due to the system being down. Despite expecting a fine, they explained the situation and were issued a new TM30 receipt without charge. Another commenter noted that experiences may vary by location.