It is common for your default Calendar reminder setting to be one day.  When ideally, this should be one hour at the least.

  1. Go to Home Screen
  2. Open “Calendar” App
  3. Go to Menu by pressing menu key
  4. Tap on “More”
  5. Select “Settings” option
  6. Tap on “Default reminder time”
  7. Select the desired time by tapping the radio button adjacent to each time e.g. 2 hours