Experiencing the same issue. My AirPods Max stopped connecting to any device. Usually it looks like this: I use it as always, then put in the case. After few hours get it again (I know it's charged) and it just doesn't work at all. None of devices can detect it. Noise cancellation button doesn't work, it behaves almost the same as if the battery were fully drain. Except it's not and indicator do react to buttons. Only after multiple restart sequences, putting to case and getting it back - it finally gets back to work and connects to my device. Takes a few minutes usually.