Issue in retrieving data from smart object with UserID and Password added to connection string

Hi,

I am having admin account with K2. I am able to retrieve the data from the smart object "process_data_audit" with the below code
            SmartObjectClientServer serverName = new SmartObjectClientServer();
            SourceCode.Hosting.Client.BaseAPI.SCConnectionStringBuilder connectionString = new SourceCode.Hosting.Client.BaseAPI.SCConnectionStringBuilder();

            connectionString.Authenticate = true;
            connectionString.Host = "abcdef123d";
            connectionString.Integrated = true;
            connectionString.IsPrimaryLogin = true;
            connectionString.Port = 5454;
            connectionString.SecurityLabelName = "K2";
           
            string smartObjectName = "Process_Data_Audit";
            serverName.CreateConnection();
            serverName.Connection.Open(connectionString.ToString());
            SmartObject smartObject = serverName.GetSmartObject(smartObjectName);
            smartObject.MethodToExecute = "List";
            smartObject.Properties["ProcInstID"].Value = "42";
            SmartObjectList oSmOList = serverName.ExecuteList(smartObject);

But, I am unable to retrieve the data if I pass my credentials along with the connection string. The code added for the credentials
            connectionString.UserID = "abcd";
            connectionString.WindowsDomain = "Domain";
            connectionString.Password = "asdffdsa@1";
Please help me in resolving the issue in getting of data with User information in the connection string.