Apple watch 5 disconnects from Peloton+ bike

Why does my Apple watch 5 repeatedly disconnect from my Peloton bike mid-ride? Typically happens 5 or 6 times during a 60 min session. I can reconnect it again and it shows the duration of the ride from the start, but (see later) creates a new record that appears as a separate workout. I have tightened the strap to ensure good contact with my wrist (one notch tighter than I'd normally wear it). It's not that I'm moving my hand or wrist either - it's stationary on the handlebars when it happens. Leaves me with 6 records in Strava that I can't combine - useless! My wife's Apple watch 5 (bought at exactly the same time) works faultlessly with the same bike so it feels like a watch issue not a bike problem. Any suggestions?