Answering a call during an activity seems broken.
Today I received a call during a run. The watch correctly showed a call notification at the top of the screen with the caller name, prompting me to hit the down button for more info. I did and the watch displayed two options - Accept and Reject. I did press the button next to the Accept option, but it didn't pick up the call. Instead it displayed another menu that looked like automated text response. One option was Reply, and I didn't remember another option.
I remember that in the past this functionality certainly worked fine.
Also, I should mention that my experience of receiving a call didn't match what is described in the manual hete: https://www8.garmin.com/manuals/webhelp/GUID-C001C335-A8EC-4A41-AB0E-BAC434259F92/EN-US/GUID-7947BE61-B96A-4F07-9E52-6C4D25775E9A.html
I didn't see icons shown in the documentation - the ones that depict the phone handset.