Erm my fertile week has moved!?

So this month ive been charting everything through glow as I have done for months and I was marking down bd days in my green week and the last green day was yesterday. Just gone to have a look at my overall month and the green days are now showing as started today and are green for the next five or so days so they have completly moved, ive not changed anything and my af days are showing as correct. Has anyone had this before?