"Can't compile the student's code" error

Hello, I’ve done fourth programming assignment of this course but I get “Can’t compile the student’s code” error when I submit my assignment. I followed instructions that you said(rename…save…refresh workplace and…even restarting kernel) but it didn’t work. I’ve done that several times and literally I submitted my assignment dozens of time…I already finished fifth week but I couldn’t fix this, by fixing solving this problem I’ll finish specialization…help plz.
thanks in advance.

Hi @reza1

Here is a link to a query similar to yours. Have a look to see if it helps.