Playback - Mercury Transmit not working

Good day,

I have a problem with Playback via Mercury Transmit to the MacBook display. Everything worked for me without any problems - I had a timeline and all windows on the external monitor, and I had a preview of the playback on the MacBook Pro display via Mercury Transmit.
Now playback stopped working for me. I've tried restarting, I've also tried turning mercury transmit off and on, unplugging and plugging in the monitor.
Nothing works. Any advice please?

Edit: I have last version of Premiere Pro and MacOS of course.