Amount of diaper left doesnt tally with amount of diaper change in IFC

Hi mummies, just curious if anyone face same thing. I always bring 6 diapers in my 4m baby’s bag to ifc. From the school app record, they usually do 3-4 diaper changes, most days is only 3. However when we go back to pack for next day, theres always like only 1 diaper left. But it doesnt tally with the amount of changes in the app. And i wonder where did all the diapers go. To the point sometimes i feel somebody’s taking my baby’s diaper. (Pls dont bash me for this) Aside from asking the teacher, which i will, just wondering if anyone face same thing