I have been using USB-C to HDMI to connect my phone to an older Samsung TV that doesn't support SmartView without any issues for a while. Recently this stopped working and neither screen mirroring nor Dex works. If I use the same set-up with my old S8 it works just fine, so it can't be the cable.
I will give this a go, thanks for the suggestion, but I still don't understand why the USB-C to HDMI just would stop working, particularly if it continues to work fine on a much older phone.
Thanks. I did and still have the same problem.