I synched a race from my Forerunner 230 to Garmin Connect on my iPhone. Later I trimmed the start time of the event in the app, and made an error, so I deleted the event from the app. The race is still in my Forerunner. But Garmin Connect will not allow me to resynch the event. My app is version 4.24.1.4. I've got an iPhone SE running iOS 13.1.2.