Same tickets. No difference in service. There is a difference in service between the budget and the flat bed class, but no difference otherwise.
As you point out, the A330 suggests AirAsia X and the fact that it’s a flight over 4 hours also suggests that; so it’s an AirAsia X flight, whatever they’re saying it as.
Judging by the general quality of their website, I’d say it’s a bug rather than anything clever like trying to sell more tickets.
Credit:stackoverflow.com‘