数据库中已存在对象Exception

我的代码出了什么问题。。。我试了好几种方法，但一次又一次地出现同样的错误。

有什么帮助吗？？代码为：

SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings[SubDomainName].ToString());
conn.Open();
string temptable = "CREATE TABLE [dbo].[Tmptablenew]([TicketID] [int] NULL,[TicketDescription][varchar](max) NULL,[TicketAssignedTo] [varchar](100) NULL,[TicketCreatedDate] [datetime] NULL,[TicketStatus][varchar](50),CRMConnectionID [int] NULL,[TicketUpdatedDate] [Datetime] NULL,img [varchar](500) NULL)";
SqlCommand cmd = new SqlCommand(temptable, conn);
cmd.ExecuteNonQuery();
SqlCommand cmmd = new SqlCommand("select * from Tickets", conn);
SqlDataAdapter adapter = new SqlDataAdapter(cmmd);
DataTable dt1 = new DataTable("dt1");
adapter.Fill(dt1);
cmmd.ExecuteNonQuery();
//BulkCopy the data in the DataTable to the temp table
using (SqlBulkCopy bulk = new SqlBulkCopy(conn))
{
    bulk.DestinationTableName = "Tmptablenew";
    bulk.WriteToServer(result);
    conn.Close();
}
conn.Open();
string mergeSql = "merge into Tickets as Target " +
                     "using Tmptablenew as Source " +
                     "on " +
                     "Target.TicketID= Source.TicketID " +
                     "and Target.CRMConnectionID = Source.CRMConnectionID " +
                     "when not matched then " +
                     "insert (TicketID,TicketDescription,TicketAssignedTo,TicketCreatedDate,TicketStatus,CRMConnectionID,TicketUpdatedDate,img) values (Source.TicketID,Source.TicketDescription,Source.TicketAssignedTo,Source.TicketCreatedDate,Source.TicketStatus,Source.CRMConnectionID,Source.TicketUpdatedDate,Source.img);";
string mergesql1 = "Update Tickets SET TicketDescription=S.TicketDescription, TicketAssignedTo = S.TicketAssignedTo, TicketStatus = S.TicketStatus,TicketUpdatedDate = S.TicketUpdatedDate,img = S.img FROM Tickets t JOIN Tmptablenew AS S ON t.TicketID = S.TicketID and T.CRMConnectionID = S.CRMConnectionID";
cmd.CommandText = mergeSql;
cmd.ExecuteNonQuery();
cmmd.CommandText = mergesql1;
cmmd.ExecuteNonQuery();
cmd.CommandText = "drop table Tmptablenew";
cmd.ExecuteNonQuery();
//Clean up the temp table
conn.Close();