I have a one-year, multiple entry visa which was issued in BKK. I attended an immigration office in Isaan to do my first 90-day report. They refused to accept my application. The officer said I have to go to BKK  [even although I am now staying in Isaan] or apply online. Is this correct? Many thanks for any advice.

I am certain you have a one year extension of stay and a multiple re-entry permit. Immigration does not issue multiple entry visas.

If you are now living in Isaan you will need to formally change your address at the designated office for where you are living to do 90 day reports. You will need to complete a TM28 change of address form and provide proof or residence.

There has been reports that a couple of offices refusing to accept the reports even after the the address change was done because they were suspicious that the extension had been done under the table. One person was forced to leave and re-enter the country every 90 days since he did not have a valid address in Bangkok to put on the TM47 form.

6. Question :  Where is the place to make 90 days notification?

    Answer :  In case of notifying in person or by agent, it must be made at the Provincial Immigration office located in the same area of the alien’s residence.

Source: Immigration website