i reschedule my program and then the workout program from in between days vanishes

I resceduled my FB 30 busy people workout from sunday 15th december to monday 16th december and the program of day 7 just vanished from my calandar

Also i rescheduled my AB 30 from thursday to monday(16th december) and the program after 16th i.e. day 6 and day 7 vanished from my calendar, i cant see day 6 and day 7 of my abs workout on my calendar now