Just saw this on the MH website:
Amongst other things:
Seems that they ended a catering contract in KL and didn't manage to get a new catering contract in place in time.
Amongst other things:
We regret to inform that all special meals, Chef-on-Call, meal upgrade, and pre-booked meals will be unavailable during this time on the affected routes.
We encourage passengers with special dietary or medical requirements to bring their own meals onboard subject to liquids, aerosols, and gels (LAGs) requirements at the departing airports on international flights.
Seems that they ended a catering contract in KL and didn't manage to get a new catering contract in place in time.