Repeating iCal entry that I can't delete

It's remarkable that the edit window has the field "show as" but not "repetition". What version of MacOS or OSX is this computer using? I'm on Sonoma (14.0) and it's the opposite.

If you still cannot get rid of the event(s) after restarting the computer you can try this other trick. Create a new disposable calendar and switch the event to this calendar. Hopefully the whole series will switch at the same time. Then delete the calendar.

I see the event you created is from midnight to midnight. You'd be better off checking the all-day box instead.

By your description I cannot say for sure that this is the problem, but let's check. Many people make the mistake of setting repeating events with the start date on the first occurrence of the event and the end date on its last occurrence. No. The end date is the end date (and time if not an all-day event) of the first occurrence. The date of the last repetition must be set separately lower in the event window.

Now for the error you're getting I can only suggest at this point to restart your computer.

Yay! Your suggestion seems to have worked. Crossing my fingers. Hopefully, those gremlins won't come back to haunt me again. Thank you!