Just a quick one, I recently mentioned a blue piece of paper I received when completing my first 90 day address report and some people seemed to not know what this was? I double checked the blue paper stapled into my passport and it is a receipt of notification. All other people that were reporting already had this notification and simply exchanged it for a new one.
TLDR : Answer Summary
The blue paper mentioned is a receipt of notification received after completing the 90-day address report in Thailand. All individuals who submit this report get this receipt, which confirms their filing and indicates the date of their next report due. Some users noted that the paper's color can vary by district, with reports of it being either blue or white depending on the location.