Try writing an extremely simple program that defines a function that does nothing but return the single value that is passed to it. Then at the top of the code (outside a function -- so you need to supply the bootstrap code in the test file) you simply call that function and go into an infinite loop once it returns.
Yes, your code works well it didn't have any issues. Also I don't think the issue is with the function or return commands as the file SimpleFunction.vm file executes perfectly. So the issue has to be with the call command only. But as far as I have debugged it, it looks fine to me.fn.asm this is the asm of your code.
update: I got my code to work on NestedCall. I reuploaded week 7 and found out there was an issue also in my function call I replaced push(f, local, i) with push(f, constant,0) as my code was only pushing the Stack pointer by nargs values and not assigning them to 0, still struggling to do FibboncciElement and Staics Test