Hi priyanka,
Than its sure you are not getting proper value in lable or the query in not being formatted well in dynamic mode. So I will request you to check the following way.
string query1 = SELECT top " + lblTotalAccount.Text + " Company_Id, CompanyName, All_Countries,All_Industries,Employees,Revenue, Status FROM SN001CompanyTable where Client_Id=100 ORDER BY [Company_Id] DESC ";
And than put a break point in the query1 and get check how does the string is being formatted. Pleas also paste the value of query1 here.
Thanks and Regards,
Rk_Hirpara.