I created this group which for all intents and purposes makes me theOnly when logged in using the same address you used when creating the group. If you've used more than one address at Groups.io, the system thinks that each is a different person.
...but it won't let me create an event in the calendar area, says IIf you can see the calendar but cannot add an event, then I think you must be logged in as a member of the group, not its owner or a moderator. Or possibly you are not logged in at all, if the group's calendar is set to public view.
As a confirmation, can you see and use the Admin button in the left column? It should be under Subscription and above Messages.
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