How do I change my af on glow for this month

My af came of feb 24 and lasted till the 28 but glow says it was supposed to start the 28 it's usually right but not this month is there a way to change it. Says I'm on my fourth day but I'm not....and when I'm expected to have af this month where I started four days early will it come on the normal day or early this month. I kno I sound dumb but I usually always start around the same time