Depends on your code, which we can't see: but somewhere, you are transferring information to the wrong instance.
When you create a new instance of a form, you need to use that new instance to "fill in" the information. At a guess - and that's all it can be without your code - you are using a static variable to hold information, or you are referring to a single instance via a variable rather than using the "new" one.
Start with the code that retrieves the values: where is it? "Parent" form? or "Child" form? How do you access the form in that code?
What do you do when you create a new form? is it along the lines of:
MyNewForm f = new MyNewForm();
FillInFormInformation();
f.Show();
If so, then you probably need to add a parameter to FillInFormInformation that allows you to pass "f"
But we can't tell, not from here. So you need to start looking!
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