My codes does not find my label control

Does anyone have any idea why this code would not find the label? It is in an update panel, if that matters. I put in a breakpoint and it was not found.
Dim label = TryCast(FindControl("lblBounces"), Label) If label IsNot Nothing Then label.Text = strURI.Substring(strURI.ToString().LastIndexOf("/") + 1) & ": " & intCount.ToString() End If
 
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