AirAsia review: Refusal to refund changed flight

On 19 April 2023 I booked a flight for 25 November for $AUS$413.27. On 28 June they changed one leg of the trip for no reason then on 5 October they cancelled the flight and informed me they had changed my flight to a time that doesn't suit me at all - I would have to miss a whole day of the conference I am attending. I spent a couple of hours that night and a couple of hours the following night trying to communicate with someone to change my flight to something convenient but there are no phone numbers, no Comments page on their website, the FaceBook page has a robot to answer, and the website only offers a robot that only uses key phrases, refuses to do what's asked, and then leaves the page. I was initially trying to get Free Change Flight but it just wasn't possible with all these barriers so I decided to try for Credit Account. To do that I had to become a member so but after I went through that process tonight 20 October and got back to 'Bo' the robot, it answered that I was not eligible for Credit 'since this booking contains AirAsia X (D7) flight" - which doesn't mean anything and is contrary to the email they sent that said I was eligible for Credit (so they would still have my money for some future flight). I no longer want to fly with AirAsia at all, they have proven that they are a terrible business. I just don't want to be cheated out of $413.27. How can I get my money back?