AirAsia keeps cancelling and rescheduling flights

I booked flights from Melbourne to Siem Reap, with a stop in Kuala Lumpur, with AirAsia back in February for the end of May.

It was all good until 6th March when an email from them arrived saying my flight was cancelled citing “operational reasons”. I had the option to ask for another flight, done. Thought i was good then.

A second email arrived some days later and a third one just 2 days ago. All of them are the same. They cancel the flight, reschedule for another but they give me the option to change it.

Has this happened to somebody else? Any advice?

P.S.

I can ask for a refund but the company says i need to process it with booking.com since i made the reservation with them. The problem is, Booking.com's customer support doesn't answer me unless my booking is scheduled in the next 5 days, because they're prioritizing customers affected by the conflict in the Middle East.