Stamp Correction.
Just a heads up, if you enter the country and get stamped in wrong, but don't notice it while you're at passport control. You can go to the immigration office out at Chaengwattana in Section K and get your stamp corrected for free.
TLDR : Answer Summary
If you receive an incorrect stamp when entering Thailand, you can correct it for free at the immigration office in Chaengwattana, Section K. It's important to check your stamp immediately upon entry to avoid complications, as failing to get stamped can require returning to the border for an entry stamp.