Currently in beta of Big Sur mac version does NOT support Garmin Express. Are you working on a fix before release of Big Sur expected this fall.
thanks
Stefan
I have the same issue. I have Big Sur OS 11.0.1 and it is not recognizing my Edge 520 plus. Tried the Garmin specific cable and that didn't work either, which was suggested by Garmin. Tried workarounds in Privacy settings but no help there. I didn't remove and then reload Garmin Express, maybe will give that a try.