What am i doing wrong specify a Date field as a parameter

I have the script below that should take screen values , put them through a processor
and then write to a database .

I have a c# program writing to a postgresql database through a stored procedure. This is a  testdabase  just to master how to write different field types to the database.. I use Dapper with my application.. Below is the script used

DatabaseWriteUpdateDeleteProccesor processor65 = new DatabaseWriteUpdateDeleteProccesor();
var outValue = processor65.TestDataRecordNumber(testcharValue.Text, Convert.ToDateTime(testdateValue.Text), Convert.ToBoolean(testboolValue.Checked), Convert.ToDecimal(testamountValue.Text), Convert.ToInt32(idValue.Text), "public.spdatatypestable_updateinsert");

[]public string TestDataRecordNumber(string para01, DateTime para02, bool para03, decimal para04, int para05, string theStoredProcedure)
        {
            string outValue = null;
            outValue = GetTestDataRecordNumber(para01, para02, para03,para04,para05, theStoredProcedure);
            return outValue;
        }

        private string GetTestDataRecordNumber(string para01x, DateTime para02x, bool para03x, decimal para04x, int para05x,  string storedprocedurex)
        {
            string outValue = "xxx";
            var parameter65 = new { testcharx = para01x, testdatex = para02x, testboolx = para03x, testamountx = para04x, idx = para05x };
            NewDataAccess.WriteData(storedprocedurex, parameter65);
            return outValue;
        }[/code]

The script  generating the error is shown below

[]try
            {
                using (var conn = new NpgsqlConnection(LoginDetails.staticconnectionstring))
                {
                    int newRecordId = conn.QuerySingleOrDefault<int>(sql, p, commandType: CommandType.StoredProcedure);
                    LoginDetails.staticmasterrecordid = newRecordId;
                }
            }[/code]



I have 5 field type (string, date, bool , decimal and integer)

Below is the debbugged screen showing the parameters fields well setup


and the input screen for the 5 field types  shown below

The script worked when i did not involve a date field.. It wrote the data to the database.

Somehow once i introduce the date field the error crops up

If any body has a script that write  a Date field to a postgre database using the method above

i will appreciate it

Thanks

Olukay