Can I Obtain a 3-Month Non-Immigrant O Visa While in Thailand?

depending on the immigration office you would need at least 15 to 21 days left on your current stamp AND you need to have 800K baht transferred from abroad into a thai bank account in your name only.

You would apply for a 90 day in country Non-O visa by meeting the proof of funds, turning in the documentation and it would go under consideration for 14 to 20 days then you would go back and get the Non-O visa and a new 90 day stamp inked into your passport.

THEN you wait until your 800K baht is seasoned for 2 months go back to the immigration office with more documents and apply for the year extension which is granted on that day..

and why didn't you apply for the 90 day Non-O visa BEFORE you used all the time from a 60 day tourist visa, a 30 day extension and now an emergency can't travel due to covid-19 extension?

What would the you be applying for a 90 day non-O visa for?