I have an issue when retrieving data from database and bind

Question

 

 I have an issue when retrieving data from database and bind into gridview

 

ISelectedDataKey = 'Gridview By month.SelectedDataKey' threw an exception of type 'System.InvalidOperationException' 

 

select IncomeType,UserIncomeDetail_Amount from ft_UserIncomeDetail inner join Dim_IncomeType on ft_UserIncomeDetail.IncomeType_Id=Dim_IncomeType.IncomeType_id where MONTH(UserIncomeDetail_Date) = @month and ft_UserIncomeDetail.User_Uniq=@Uuniq;

 

in above command i am passing the integer value like month having like 09,08  when executing command prompt it getting data but when selecting month from dropdownlist it's throwing error  pls fix it