更新数据时提示 ORA-01008: 并非所有变量都已关联 错误.请人指点错误在哪里

  string xinpassword = FormsAuthentication.HashPasswordForStoringInConfigFile(xinpwd2, "MD5");
                string nbxh=Session["nbxh"].ToString();
                string UsrName=Session["UserName"].ToString();
                string sqlupdata = "update HYW_USRENAMEINFO set USERPWD=:pd  where NBXH=:nbxh";
              //  OracleCommand cmd = new OracleCommand(sqlupdata,conn);
              //  OracleParameter oraclepare=new OracleParameter();
               // cmd.Parameters.Add("pwd", OracleType.VarChar).Value = xinpassword;
               // cmd.Parameters.Add("nbxh", OracleType.VarChar).Value = Session["nbxh"];
            
               // conn.Open();
               
             //int a = cmd.ExecuteNonQuery();
            // if (a > 0) {

              //   Response.Write("<script>alert('修改成功');location.href='frame.aspx'</script>");
               //  Response.End();
                    //}
                OracleCommand cmd = new OracleCommand(sqlupdata, conn);
                OracleParameter[] paremeterArr=new OracleParameter[]{
                  
                  
                    new OracleParameter("pd",xinpassword),
                    new OracleParameter("nbxh",nbxh)
                  
                };
              
                conn.Open();
               int a= cmd.ExecuteNonQuery();

 if (a > 0) {

                 Response.Write("<script>alert('修改成功');location.href='frame.aspx'</script>");
                 Response.End();
               }