How do you delete invites on your iPhone calendar?

[Skygirls]

My friend sent an invitation on the iPhone which went straight to my calendar.

I accepted the event and now that it has passed, I want to delete it from the calendar, but there is no option to do this?

Does anyone know how?

TIA

go to calender, find the event, double click, chose edit, scroll to the bottom then delete event.

Tried that and didn't work- no option to delete comes up.