the number of items was 79 in my weak kanji and i did 2 or 3 week kanji tests of 15 items but it only went down to 78. I know if i got them all wrong then that would make sense but i answerd a good amount correctly. any way i am gonna check again now
no, there is nothing wrong but just the reordering system can be kind of confusing.
When you are doing weak quiz, the item will be reordered every time you answer item. so, after finishing 15 items, that does not mean you cleared 15 items, but some of the 15 items will be reordered to the less weak item near the end of the list.
I'm sorry for the confusing system, I hope you can understand my explanation.