There could be many reasons, e.g., she may not have enough money in the bank to support herself independently. She may be a signatory to your account, but it is not her account. Visitors to the USA usually can not work; if they do, they get deported at great expense. Hmmm? It's the same in Australia and many other countries.

Like they say "When all else fails read the instructions".

I have only had OA retirement visas several years apart before COVID-19. One of the bonuses of getting an OA visa in your home country is you can only get in your home country, that can allow you to stay in Thailand for up to 2 years, the first year on a retirement visa, the second year is an extension (you cannot get an extension with an extension) and the Bt 800.000 in your home country bank account is yours, you can do what you like with it. There was no fee for the 12-month extension. That was my experience some years ago. I believe it is now the same but you have to have insurance for medical cover now. a modest cover approved by Thailand. Also, you have to fill out an application form which has some requirements at the Thai Embassy. I have never had a bank account in Thailand for 15 years, there are ways around that.

Perhaps, if you apply for a Thai OA retirement visa in your home country you do not have to have a bank account in Thailand. It is required that you have the Bt800,000 in an Australian Bank, not in a Thailand bank. That is my experience. I have previously had 2 AO visas using simply an Australian original bank statement (not a copy but an original statement only).

@Stuart ********

For the OA visa that takes care of the first year full year, it is usually a multi-entry visa you get in your home country, the 2nd year is an extension, and it is not multi-entry, you get that from Thai Immigration like most extensions. With a multi-entry visa, you can leave Thailand but this will be the conclusion of your 2-year stay. getting a 2nd extension if you can get would allow you to stay in Thailand on a single extension. I have not heard of this. One multi-AO visa with one extension In my experience you only get one extension the 2nd extension is not available, you can only get one extension on an OA visa from your home country for which you can only stay 2 years total, a 2nd extension would make it a total of 3 years. I stand corrected?

That is if you can get an account?

You will not do much good until you have had at least Bt65,000 amounts monthly over the last 12 months deposited. That is proof. Even that may not be accepted. Nearly Bt800.000 after 12 months. I suspect you are required to have that Bt800,000 in your bank as you apply for the visa. immigration can give out visas at their discretion.

Yes, I have been to Thailand from Perth W.A. in recent times on a visa exemption and a 30-day extension. I think that is enough for me. I've been 2 times already so far. That's all OK for me.

@Jim *******

... I addressed the situation of a farang in the 3rd person I did not use any name on purpose.. I did not address anyone except a multitude of new persons, farangs who would like to own real estate in Thailand, condos, businesses,, shops etc. They are all in that category and appreciate guidance. Go and troll anywhere else you like.

Ruth Regal, The OP seems to have deleted his post, so we are communicating about something now that can not be verified...end of story.