I just got an email from Kasikorn about changes to the Terms & Conditions of the account. I found there was an update to the KPlus app, so I installed it.
I now get the "request temporary limit" option, but it says my max limit per day is 5,000,000 baht and I can change the daily limit up to 5,000,000 after completing a face scan.
Sorry about the grainy image, which I took with another phone and a shaky hand.