I tried to pay my True internet bill online but the bill reference has 13 digits and the Kasikorn system comes up with a message saying it accepts up to 12 digits. I continued with my customer account no. which is 12 but in the end I didn't hit the confirm button as there was only one set of reference details.

Anyone else using this and having the same problem?

Do not use but did use BBL phone banking and had no problem with 13 digits so you might try using the phone service of Kasikorn and see if that works.