Why is that only the future events can be duplicated, but not the past events?

Trantor said:

Why is that?

Probably because you did not create the event yourself. You can only duplicate your own events, and you can then duplicate them even on the Past tab.

Trantor said:

Also, is there a way to make an event recurring, say weekly?

No, events can have only one date, currently.

If you want to create an event just for yourself, then you could create a Workout instead, and then schedule it each week, or just upload it to the Workout library on the watch, and execute it whenever you wish. 

And if you need it for a group of friends, then you could schedule multiple workouts for them using the Garmin Clipboard app.

Thanks Trux. I had created the event. Both via GC Android app and via the Web, I do not see the option to duplicate a past event.t.

Trantor said:

I do not see the option to duplicate a past event.

I have it here:

Interesting! I only see the option to remove from the calendar.

Strange, I see this event menu only at events that I did not create myself. Are you sure you created the events from the scratch yourself, not using some existing official events?

I will do some more tests later, and let you know if I find something

Indeed, I created these events my self. These events are for a weekly parkrun.

Only for future events, it shows the option to duplicate (and that too via the app and not via the web).

When I review the JSON data of the events using browser's DevTools, I see two differences between those that can be duplicated, and those that cannot. I can duplicate past event where the property "eventOrganizer" is set to true, and they have also "eventPrivacy" set to "PRIVATE" (though I do not know whether the later plays a role or not).

You can try opening the page in DevTools of your browser, and on the Network tab, checking the stream "events", and then verifying how those values look like at your events.

Thank you for taking the trouble to investigate. For me the eventOrganiser is set to false and under eventPrivacy, its a sharable event..

I created a dummy event and marked it as Public/Searchable. One saving it, there was no option to duplicate. However, when I make it private, there was an option "Duplicate" for the active event. I will check again tomorrow (when the event is in the past) if the Duplicate option is still available.

Its strange that events marked as public cannot be duplicated.

Hopefully someone from Garmin Support can comment on why public events (created by me) cannot be duplicated.