为多个值保留相同的自动增量ID

I have a table in my database called university with 3 columns: 'uni id', 'uni name' and 'student id'. I've added an auto increment value, the 'uni id'. When a student select the university name (let's say 'University A'), the ID should be 1 and the 'student id' will be updated with the id of the student. That's fine. But if another user selects the same university ('University A'), the 'uni id' will automatically change to 2 (obviously, it's an auto increment value yep). The 'uni name' will stay the same 'University A' and a new student id will be inserted in the table. I have a table in my database called university