The Calendar

Liz
I have it set for my period is 5 days 26 days apart but my calendar still says I should be on my period it's been on there for 10 days and only five of them I actually was on my period. How do I fix it? I have already tried going to "edit" and it's set to the five days I was on my cycle but once I hit save and look at it, it's back to 10.. How do I fix it??