iOS EBC: no HR records via Fenix 6X Pro and Garmin dual-band HR strap

HR shows as connected on the setup page listing all the sensors, each one of which is also showing as connected. However, when I start the exercise itself, HR does not show on the screen. On the 6X I have selected the Garmin option of “Bike Indoor” and the “Smart Bike Settings” and I’ve setup the data screen to include HR. While actively cycling, HR shows, but it the “heart” graphic is greyed out. I don’t have a clue about what I’m doing wrong.

Reddit has nothing and Garmin Forum has nothing. And the same output is true with the standard BT Garmin strap. Since Ive had a history of PSVT’s using Tabata protocols, the signature symptom is HR accelerating during the rest interval beyond the ordinary delay in showing a reduction. So, HR is the most critical metric for me,

Thanks in advance for any input, Anthony