student should not select same course in studuent edit page

i have one doubt a student should not select 2nd time same course in student edit page how to do this 
1 answers

Hi Abbas,

Could you provide us with a bit more information on what you are trying to achieve, and what goes wrong? I assume it is an assignment in one of the academy courses, but (at least I) don’t know all these courses and questions by heart :)