The call( function needs to be used like any other function. It needs to be part of a statement. It can’t be the whole statement. It might be something like
SomeVariable = call("","FunctionValueProc",LList)
Note that FunctionValueProc is quoted.
Just like any other function, Panorama needs to be told what to do with the value returned by the function.
If all you want to do, is to call a procedure that will perform some action, but not return a value, you need to use a call statement.
call FunctionValueProc, LList