High School is continuing after the normal ending time.

Hii! I was playing the High school sims 4 expansion pack and it going as normally but when it hits the second class for some reason it will continue after 3pm for some reason I don't know if it's my mod or my game is broken. Also there are times when the Sims are in high school they are in break. It would be like that for many sims hours and it would be glitch. I don't know why this happening.