Double click on Apple Calendar's event, a new event created instead of popping up event details

Hello everyone,

This has been a annoying little thing for a few years now.

Apple calendar is the very main production planning app for me, but there is one little annoying bugs/ whatever it is that decrease a lot of my working flow.

Normally, when you are using the Apple calendar, when you double click on a event, the details/ info of the event will pop up, and allow you to change the event name, calendar type time and else quickly. (which is very fluent on the work flow)

And you could just use OPTION + mouse drag to duplicate a event on the calendar. (another smooth work function)

BUT!

BUT!

Somehow, sometimes there will be events that just cut you from doing this.

When you double click on these random events, instead of popping up a event details/ info, it just create another blank event.

and if you try to OPTION + mouse drag these random events, instead of duplicating, it extend the events.

Is there anyone out there who's suffering from this?

And if this is a known BUG that has been haunting people for ages?