Multiple Result reading is very slow.

when i use Query Multiple with Store Procedure and read results one by one then i notice that first result get read very fast but next result takes too much time to read. because of this performance we get is poor. please advise weather i am making something wrong or is there any way.
my code is as following

using (IDbConnection conn = new SqlConnection(connectionString))
{
var reader = conn.QueryMultiple("GetSalesData", new { @Request = RequestValue }, commandType: CommandType.StoredProcedure);

                        var UnitPriceList = reader.Read<GetItemDetailsEntity>().ToList();
                        MC.UnitPriceList = UnitPriceList.ToList();
                        var QFRList = reader.Read<GetItemDetailsEntity>().ToList();
                        MC.QFRList = QFRList.ToList();
                        var DispatchList = reader.Read<GetItemDetailsEntity>().ToList();
                        MC.DispatchList = DispatchList.ToList();
                        var ProjectedDispList = reader.Read<GetItemDetailsEntity>().ToList();
                        MC.ProjectedDispList = ProjectedDispList.ToList();

                        strReturnData = ObjectSerializationService.ObjectToXML(MC);
                        return strReturnData;
                 }

Start with the supplied QueryMultiple example and profile the GetSalesData stored procedure alongside each reader.Read() call. No repository file, test, schema, or reproducible timing is provided, so first determine whether the delay is in Dapper or the stored procedure. Done means identifying a reproducible cause and documenting or testing the resulting fix.