This is just an indication that the color bars on the month view are not all that are assigned to the given day. Tap the day and you will see all the elements there.
Ok now i understand. thanks can i plz ask u something else...i' m trying to reschedule my training plans days but i'm not seem to manage..i can't drug and drop the 6th of month to 7th...do u know how can i do that exactly