This is the second day in a row that the Garmin Connect Activities & Calendar are not displaying. I like to upload my workouts and do quick edits in the Activity view. Calendar view is one of my favorites because I see what I've accomplished. Screenshot attached.
Strange.I don't know why you'd see am error message couched in the Classic view inside a Modern frame.
For what it's worth, I haven't had any issues with Garmin Connect online in the past few days, and I've been uploading and reviewing new activities during that time.