I feel bad for so many Jews who fasted on Yom Kippur and felt falsely that they received forgiveness [and I hope that I am not one of them].
They didn't. They will be surprised after 120.
The Gemara [Yoma 86] says that when one is מחלל השם, Yom Kippur doesn't bring atonement. Only Teshuva, Yom Kippur and DEATH [!!!] help.
I am not pointing fingers. Hashem is the מלך המשפט. He decides. Not littly eensy weensy puny me. But I am writing this in order that we all examine OURSELVES to make sure that we are not מחלל שם שמים in any way, shape or form.
If we act in ways that don't reflect the pasuk דרכיה דרכי נועם וכל נתיבותיה שלום - If we are not pleasant and peaceful, if we make Torah ugly in people's eyes [CHAS VI-SHALOM], there is no kapparah in this world.