There’s often a thousand different reasons why macs and third party devices like ours don’t communicate well. But the one’s that worked for me recently and often aren’t mentioned, are the cables/dongles. I had genuine apple USBA-C dongles that didn’t work. However, I tried an old genuine apple USB-C Digital AV Multiport Adapter and it works perfectly every time. I’v e also heard rumour of USB 2.0 accessories being more successful? Try every combination / permutation of USB 2.0, 3.0, 3.1, cable, dongle, powered /non powered hub type dongle, expensive apple certified, cheapo knock off brand…