One of my sims keeps resetting near the end of his school day and ends up back home. I've uploaded a script error. Could someone please tell me what his problem is. Thanks

System.NullReferenceException: A null value was found where an object instance was required.
#0: 0x00005 callvirt in Sims3.Gameplay.ChildAndTeenUpdates.Sims3.Gameplay.ChildAndTeenUpdates.Punishment:GetBuffOriginForDeviantBehaviorType
(Sims3.Gameplay.ChildAndTeenUpdates.Punishment/DeviantBehaviorType) ([1] )
#1: 0x00021 call in Sims3.Gameplay.ChildAndTeenUpdates.Punishment+DeviantBehaviorInstance:.ctor
(Sims3.Gameplay.ChildAndTeenUpdates.Punishment/DeviantBehaviorType,Sims3.Gameplay.Utilities.DateAndTime) (930D0A5C [1] [vt:930D0A44] )

You have a "deviant behavior" for teens mod in play? Not to be judgmental or anything, but that sounds out of character.

I was going to guess icarus' scolding/punishment mod maybe at fault, but seems like you don't have that one (or it's not showing up in the usual place). Might the teen in question, Byron Witherspoon, be having a mood swing?

LOL you're right I don't have a deviant behaviour mod. And I think Byron was having a mood swing. His traits also include rebellious if that makes a difference. He's reset a couple of times but not sure if mood swing was involved the other times. Why would his mood cause a reset? This would be a first for me. I had him scheduled to text his steady girl after school to break up because she aged up to YA and he's still a teen.

Also, l don't have the scolding mod.

Would he by any chance be grounded?

No, I don't play with scolding. I thought it may have something to do with him going steady with YA while he's a teen. I don't have adult/teen relationship enabled.

Trying to do the Break Up text might be the problem.
By game default even with adult/teen relationships when one ages up while the other doesn't they revert to romantic interests.
Without adult/teen relationships enabled they'll have to wait until they are both young adults to resume their relationship.

I thought that's what they were suppose to do but they didn't. They maintained their steady status, that's why I as a having him break up with her. Also another strange thing happened with another teen in same family. His romantic interest aged up and he didn't. So I had him invite this now YA female over so he could ask to be just friends but before he could ask she asked him to go steady and the little idiot accepted LOL. Now I had to break them up! I'm confused with all this because it's not suppose to happen.

Try sending the text while he's at home it could be the game trying to push the interaction before he leaves the school building. Or you could just use MC and change their relationship to best friends or friends and avoid them disliking each other.

I would have voted for the MC method myself as sittingbear says and avoid all the heartache and confusion. Or at least some of it. But littlelambsy, are you still playing with bluegenjutsu's more autonomous romantic interactions mod? It's awfully unusual otherwise for an inactive sim to ask one of our actives to go steady, especially if they are not what the game calls age-appropriate.