Correct,thats why I said some. There are 44 countries just in Europe with embassies and consulates in Thailand. Not every country has a totally useless embassy like the US which has almost stopped issuing any type of certificate for US citizens.
We're talking about for example travel agents for heavens sake. They are everywhere in Bangkok and in other major cities. In what neighborhood are you located?
Then I guess you need to certify/legalize a passport copy back home or maybe in a neighboring country where there is an embassy or consulate.The MFA won't probably accept this to be done by anyone. Same with the marriage license.
The last time I changed my passport number at KBank it took maybe 15 min. This was at KBank in Jomtien. A new visa debit card took 20 min tops. Same bank. 20 min at Bangkok Bank to change the passport number. The longest time at a customer service desk was 40 min at Bangkok Bank in Jomtien when I renewed my Fixed Deposit Account, which is basically opening a new account from scratch.This is not a cause for a heart attack. When you go to your branch you can plan ahead and be there maybe 15min before they open. If you are no 15,then yes, it will take time.
Where does it take 4 hours to change anything connected to your bank account? Stop posting nonsense. Maybe you don't understand how and why you need to do it.