ITA multi city origin no longer work
In the past I always searched ITA matrix for fare using multiple airports as origin because they are near my home. However it no longer works. I'm trying to search an itinerary starting from HKG,CAN because they are Aeroflot destinations near to my home, but ITA matrix now pops up "Multiple JOCs found in slice 0, constrain origins to a single country" such that I can no longer search for fare.
How can I make it work like before?