What should I do if I have a transit visa and need to apply for a teaching position in Thailand?

Hi all. I am currently in Bangkok and I have a school offering me a place to work as a teacher. To process my documents with the MOE they have to send a letter, however I have a problem.

I have been in Thailand since April and i visited here before Christmas last year. I have used my two land border crossings and when I tried to get a tourist visa from Savanakhet I was denied and given a transit visa. Also when I flew in from Da Nang in May to Suvarnabhumi airport I was questioned by the IO, eventually they let me through but they asked me many questions.

According to my school, I cannot apply to the MOE on a transit visa, so they have advised me to go to another country for around 5 days and then fly back to Thailand for a 30day waiver stamp. However I am concerned that they may deny me entrance as I have been here a while already.

Does anyone have any advice? If I fly to phuket or chiang mai are the IO's less strict?

Thanks 😊