I experiencing this issue (I think a known one) on my Garmin account.
I have a Garmin Fenix 5 that I use only for walking and swimming activities. And an edge 1040 solar for cycling. I have now a Garmin Pro HRM and a Shimano power sensor.
The VO2max is no longer updated since the 23th of March. And the trianing load no working on my edge 1040 since a long time.
I've tried to remove the Garmin connect app on my iPhone, unpair all devices, hard reset also devices. And then reinstalled + connect all to Garmin connect; It doesn't change, Garmin Connect says "No status", my 1040 too.
I have an iPhone 14 with last updates for iOS and Garmin connect