replace
;
with
,
string command = "update info_ash SET name = @Name, roll = @Roll, hometown=@HomeTown, twitter=@twitter, birth_year=@Birth_Year, birth_month=Birth_Month, birth_Date = @Birth_Date, b_g = @Blood_Group, religion = @Religion, facebook = @Facebook_id, mobile = @Contact_no, email = @email where id=@id";
and add the parameter id with all other parameters
cmd.Parameters.AddWithValue("@id", search.Text);