How to Replace Link URL in PDF?

My Code like this:

if ((goToAction.URI).Contains("DeviationAudittrailPdf/ExeDeviationAuditDetailsPDF.aspx?DeviationID="))
{ 
//a.URI = a.URI.Replace("DeviationAudittrailPdf/ExeDeviationAuditDetailsPDF.aspx?DeviationID=", "/Execution/ExeDeviationAuditDocViewer.aspx?DeviationID=");
}

@Karthimani

Is this URL assigned to bookmark or any annotation? Can you please share your sample PDF for our reference so that we can test the scenario in our environment and address it accordingly?