12 Year Old In 6 Not 7

So I was scheduled to fly with jester too to Melbourne from Hobart. I turn up at the airport and the guy asks me all the questions how old are you etc, then he asks me what grade I'm in i say six and he says I'm sorry you can't fly i had two other flights connecting to thailand and then too germany it was unbelievable so they'll let a 12 year 7 go on board but not a twelve year old year six. The even more ridiculous thing is i had just finished year six literally the day before i even had a orientation day in year seven doing all the subjects and every and i have too say i do not look that young either. still to no avail he would not let me onboard he wasn't even sorry afterwards he just started laughing and mucking around. i mean my dad and i booked a ticket 2 weeks before and it stated nowhere on the print that you had to be year seven and also that year we booked a ticket with them then entered some number wrong with the ticket purchasing and they held 600 dollars of our money for 14 weeks. Anway getting back to this main story there is now only 3 airlines flying out of hobart and virgin was full jester was full andy i had to forfeit my fair quants was the only one left. 550 dollars straight out of pocket just too melbourne I'm looking forward to the day they expand hobart airport probably not for ages though. therefore you should never ever book or fly with jetstar