Universal control between mac mini m1 and macbook air m1 keeps losing connection

Hello,

I wonder if anyone else is having trouble keeping a stable universal control connection.

I am connecting a Mac Mini M1 with 2 monitors to an M1 Macbook Air. After a reboot it will usually connect and work for a while, then disconnect and never reconnect again.

I do have a TunnelBlick VPN connection on the Mac Mini most of the time, and I wondered if that might be interferring with the connection, however I have tested without the VPN for a while and it didn't seem to rectify itself.

I have checked all the requirements for systems settings, hand-off etc are correctly applied.

Any other ideas?

Thanks