I have encountered a similar scenario as yours. I tried everything i could think of. Even created a thread regarding the issue.
What i found that worked for me was to move the devices to a new Network. That seemed to make all devices begin communicating again. P.S this is a temp solution, would like to see what the devs think about this… Its a problem that we need to sort out ASAP
Here my Post (Still waiting for anyone to give me suggestions )
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