Unable to close QC connection

Dear Support,

I am using below line of code in C# to update test case status but after execution it doesn't close connection. It creates new connection each time. Please let me know how I can close connection after execution below line of code.

try
{
        QCConnector.QCConnector objQCconn = new QCConnector.QCConnector(qcUrl, domainName, userName, passWord, projectName, folderPath, testsetname);
        objQCconn.SetTestCaseStatus(testCasename, QCConnector.QCConnector.Status.Passed);
}
catch (Exception ex)
{
        Log.WriteLog("QC Error :"+ ex.Message );
}

Thanks & Regards,
Rajeev