Lil Baby recently cancelled his set due to illness he later specified in an instagram apology to fans who attended the Vancouver’s Breakout Festival. He was supposed to end the show with the last 30 minutes or so, but had to cancel. Fans got mad and started to destroy the venue. Because people think if they don't get what they want, they have to act like this. I'm sure they would have someone else come back and do something to make up for their headliner having to leave.
But, I think it was partly due to other also cancelling their set during the show, those being; Lil Uzi Vert, Polo G, and Sofaygo. The venue hosting the event is looking into refunding some attendees. But I doubt they will refund anyone who started destroying things.