can't access hidden filed value in target form

In form1.aspx I have a hidden field.I am populating the hidden field with the value in the text box.
When I go to form2.aspx i retrieve the hidden filed value in another hidden field using request.form.
After using request.form ,the value is empty.
what can be the problem here?
In form1.aspx:-HiddenField1.Value = TextBox1.Text;
In form2.aspx
HiddenField_2.Value = Request.Form["HiddenField1"];
 
Please help.

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