What should I do if my non-O multiple entry marriage visa has a stamp limiting my stay to 90 days?

Agree 100% with what has been said. There may be a third option, an extension based on employment. This would include a work permit and all the proper documents from your employer, and perhaps even proof of tax paid. Technically, it could even be your own business. The 60 day extension above may or may not give you time to get papers together. But, it could be a third option.

The Immigration Officer was correct.

You had a multiple entry Non O Marriage to Thai visa.

Its only good for 90 days on arrival .

To get another 90 days you need to leave and return to Thailand...which with borders closed...not possible.

Your option...

Get a 60 days Family.visit extension at end of your 90 days..

And follow the steps to obtain a one year extension as described above.

Good Luck.

A non-O multiple entry visa based on marriage to a Thai national is valid for one year. However, on each entry, you are given a stamp allowing you to stay for 90 days. You have three options:

1. Acquire a one year extension of stay based on marriage to a Thai national. This will require banked money of 400K THB in a Thai bank account seasoned for two months, or monthly income of 40K THB a month; among other requirements.

2. Acquire a 60 day extension of stay based on visiting Thai family. This does *NOT* require any proof of income or savings. Some immigration offices allow you to get this 60 day extension of stay once PER ENTRY, and others let you get it once PER VISA.

3. Leave and return. If you leave, you'll have to repeat the process of getting a Certificate of Entry, and quarentineening for 15 days.