When using Spectator Messaging on either my Edge 840 or Forerunner 945 LTE (with bluetooth connection to my phone), I often find that I do not receive Spectator Messages at all during the activity, and instead get them at a later date when starting a new activity. I have been able to force it to send the most recent message by opening the Garmin Connect app on iOS (while the activity is still happening on the device), force quitting the app, and relaunching it. However this doesn't fix the issue, as if I want subsequent messages I need to force quit it each time.
I've also tried deleting and reinstalling the app, and resetting network settings on my iPhone, but neither fixes the issue