still don't understand why mine was reject though. I did ask at IO when I went to do it in person, I typically got the shrug of the shoulders and standard answer of "not know".
I tried 3 times last week and it binned me 3 times for all the same reasons, date of entry into Thailand and date of VISA expiry. I know for a fact all the information I submitted was correct. The ONLINE system is completely hit and miss. I'm going back to visiting IO in future