How to delete the AD from ios schedule

I’m very bitter pill by ad from ios schedule,even I delete the ios schedule event invite,but the event still exist in omnifocus, How to delete them, this ad will cycle every week.I hate the ad exist and remind me again and again, if this ad can’t remove, I have to give up Omnifocus, this is very furious for me.

This sounds like calendar spam. There are many ways to get rid of it. See the instructions in this article.

If it’s easier to see what to do, try this YouTube video on how to get rid of calendar spam.