'cancel all changes' total lie and misconception

Greetings,

I had a domestic return flight booked from Brisbane to Sydney.

I wondered what the cost would be like if i made a change to this booked flight

I logged on and made temporary flight changes, when i was on the screen :

Booking Details It has the option

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Jetsar Airways - Cheap Flights

Please review your changes carefully before finalising your booking. You can cancel your unconfirmed changes at any time by clicking 'Cancel all changes'. Any changes made to your booking will only be finalised once you've paid the amount due

However there is no cancel all changes button. It wasnt there, I went back to the previous page hoping it wouldnt stick but guess what it did.

I have now lost my flight and bought a new ticket at an additional $220 cost.

I rang the call center and first they said they would stop the$220 payment but I would lose my original booking, I said I wanted my original booking because i never confirmed changes ever, when I asked for a reference number they hanged up on me.

Whats worse is the screen is still showing Amount Owing...this proves my point I never confirmed it, they say it has, they dont believe me.