You might need to find small ways to strengthen your application if you apply again, to ensure you get approved next time.

Cambodia I read is taking some time, HCM can be more picky with documents, did you think about Hanoi?

I would highlight parts in your bank statements and other relevant docs where it states your name, account number, income payments, the 500k deposit if it’s deposited within the statements. You need to show the 500k balance and the ongoing income received, matching your payslips. If you don’t have this in the same bank account, then submit 6 months of bank statements from the 2 banks.

I would also write a formal cover letter to inform them of your intentions in Thailand, why you like it there and want to be there, how you’ll financially support yourself, where you’ll live, that you won’t work in Thailand and list the documents you’re including with your application.

For your company letter ensure it states you are allowed to work remotely in Thailand.

One longer post I wrote about my application