No error is thrown and app fails to work when year is provided with valid track

[LiuYJ2002]

User executes add n/B s/MATH e/88888888 a/Newgate Prison p/1234567 l/S5 NA s/ENGLISH lt/SAT-11:00-13:00 lt/SAT-11:30-13:30

User uses l/S5 NA. which is valid according to user guide.

From the above picture, the command could not be executed and no error message is thrown.

Only error is thrown in the terminal as seen below

[nus-pe-script]

Team's Response

dup

The 'Original' Bug

[The team marked this bug as a duplicate of the following bug]

Functionality flaw of S5 NA

It is mentioned that for the level, we are allowed to use S5 NA. S1 NA works

S4 NA works However, S5 NA refuses to work for me

---

_{[original: nus-cs2103-AY2425S1/pe-interim#1857] [original labels: severity.Medium type.FunctionalityBug]}

Their Response to the 'Original' Bug

[This is the team's response to the above 'original' bug]

valid. good job on spotting this :(. This is caused by the way (or lack thereof, hence the null pointer exception) we validated subjects for S5 NA.

Items for the Tester to Verify

:question: Issue duplicate status

Team chose to mark this issue as a duplicate of another issue (as explained in the Team's response above)

• [ ] I disagree

Reason for disagreement: [replace this with your explanation]

---

## :question: Issue severity Team chose [`severity.Medium`] Originally [`severity.High`] - [x] I disagree **Reason for disagreement:** Reason for Disagreement: Thank you! However, I would disagree. If I am a private tutor teaching only `S5 NA` students or some `S5 NA` students, I would not be able to `add` them with `level: S5 NA` in the app. **According to the UG, if I cant add a student with a `level S5 NA` I would not be able to add `subject` and also a meaningful `lesson timing`.**  Thus this defeats the purpose of the app if the user could not add his/her students with the `level: S5 NA` due to the failure of `add` command as they could not use the many other functionalities/commands of the app that requires a level tag to help him/her manage their students. The user could also not use the find command other than by name. Therefore, I would argue that it is not `severity.Medium` as it is **not just occasional inconvenience** created as the user could no longer use the app for the purpose it promised. 

---