Same thing with AW series 4 and late 2019 27 inch iMac. Managed to get through to Apple support, but as part of the diagnosis, I was asked to reboot my phone. The support person promised to call back, and did. but when I answered, after a mere two rings, all I got was "sorry we missed you." I managed to get a case number early on in the first call, but all forms of Apple Support have been unavailable since I got off the phone early this a.m. CST. This is obviously a terrible day to work in Apple Support. If a fix doesn't show up in the forums or elsewhere in the next couple of days, I'll try calling again. Meanwhile, I've tried everything I can think of except for unpairing and re-pairing the watch, which is more hassle than I have the patience for right now.