unable to add new students into my classroom

Hi, I was just trying to add a new student into my classroom.

However, when I clicked the "add" button, it turned out to show "500 Origin Error".(See screenshot below)

I also tried relogin and used differents computers and laptops but all in vain. All I get is "500 Origin Error".

Please kindly help me solve this problem.

I really need to add my students into the classroom!

Thank you.