Error no value given for one or more required parameters.' select from excelsheet

When i try to get data from excel sheet i get error

no value given for one or more required parameters.'

why this happen

i work in visual studio 2010 with excelsheet 2013

my code in c# as following

public DataTable ShowWrongExcelData()

	       {

	           string connectionString = string.Format("Provider=Microsoft.ACE.OLEDB.12.0;Data Source={0};Extended Properties=\"Excel 12.0 Xml;HDR=YES;IMEX=1\";", txtPath.Text);

	 

	           OleDbConnection con = new OleDbConnection(connectionString);

	 

	 

	           con.Open();

	           string str = @"SELECT  [??? ?????????] as [UnitCode],[????? ??????]as[CurrentMeterReading] FROM  [Sheet5$] where [CurrentMeterReading] <= 0 ";

	         

	           OleDbCommand com = new OleDbCommand();

	           com = new OleDbCommand(str, con);

	           OleDbDataAdapter oledbda = new OleDbDataAdapter();

	           oledbda = new OleDbDataAdapter(com);

	           DataSet ds = new DataSet();

	           ds = new DataSet();

	           oledbda.Fill(ds, "[Sheet5$]");

	           con.Close();

	           System.Data.DataTable dt = new System.Data.DataTable();

	           dt = ds.Tables["[Sheet5$]"];

	           return dt;

	 

	 

	       }

why give this error i don't use any parameters

but when i select all data from Excel sheet as following :

@"SELECT [??? ?????????] as [UnitCode],[????? ??????]as[CurrentMeterReading] FROM [Sheet5$]";

I get data without any problem

so that How to solve this error please ?

Excel sheet InvoiceData.xlsx sample

http://www.mediafire.com/file/b62b5ub26mrt9t1/InvoiceData.xlsx