Can't figure this out

It added on here automatically that my period was the 1-5 I haven't had a period yet but it also won't let me delete it. It says period days can't be deleted or something like that. If I can't fix it I don't know if my ovulation/fertile days are correct and we've been trying for 5 months and I finally found out about this app lol I really hope it works! Any help would be greatly appreciated!!