I can not access control of window form from another class in c++

[Sanjay12]

i have some forms and one class(queue) in my project and i want to take the information of window form(Add.h) from class(queue) but when I include form(Add.h) in class(queue) and create object of form then it show that identifier "Add" is undefined.
2017-12-17 (1).jpg