O-A Extensión issue. Any advise please?

My last entry stamp expires on 7-8-20 so in readiness to extend I just went to visit Mukdahan immigration to finalise their exact requirements and evidence.

I have health insurance so no problem there.

The problem is their idea of the money requirements. I understood that I had two options a) 65,000 a month for the previous year or b) 800,000 for two months prior then three months post renewal.

My choice was option a) and I have transferred 70,000 every month via TW from the U.K. to my Bangkok Bank for one year.

They are not interested. They just kept on about embassy letters and proof from the U.K. government of my income.

I explained I am not old enough for a pension and I do not work. This is my own money.

They will only accept the 800,000 method but I only have one month of my stamp remaining so I can’t do that.

The IO suggested a border bounce but I believe nobody is allowed back in. The IO didn’t seem to care.

What are my options please?