Uh, you can't really expect to post barely two sentences and expect everyone to understand what you're talking about and be able to come up with some conclusion.
By the very little I have, the only thing I can think of is the fact that if your iOS device is being synced with your calendar, it will pop up a notification at the start of your event. There is no way to turn this off, that I am aware of, but it only pops up right at the time of the event and not ahead of time like alerts.