Why did the embassy request additional bank statements despite meeting the 500,000 THB requirement?

Laos, soft power

I submitted my documents on Thursday, paid the fee on Friday. Received a request for more documents today. They requested 3 months bank statements, whilst I submitted 6. I have several bank accounts and I only submitted the bank statement of the account that has more than the minimum 500,000 THB (almost double that). That account is just as a kind of back up, so has no debits or credits, as I don't use it for anything. So the document was only one page showing the time period and the balance throughout that period). Why would that not be sufficient?

I now added a second bank account's statements, but that account doesn't have the minimum amount of 500,000 THB. Combined it obviously does exceed the amount required. Both accounts are in my private name.

Anyone has had something similar? Thanks!

EDIT: I got approved without any interview. I submitted an additional bank account with less than 500,000 THB, but showing expenses and income. I also submitted a short letter explaining that the other bank account has no activity and highlighted the period of the statememt to make it extra clear that the statement indeed was more than 3 months.