I am getting error saying ord2.MOD_Email_Sent_Date_DR__c this is not valid variable.


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public static void update2WeekPickList(List<MOD_Order_Detail__c> ordetaillist)
   {
       Set<Id>OrderDetailIds=new Set<Id>();
       for(MOD_Order_Detail__c ord:ordetaillist)
       {
           OrderDetailIds.add(ord.Id);
       }
       List<MOD_Order_Detail__c> ordetaillist2=[Select id,MOD_Email_Sent_Date_DR__c,MOD_Week__c,(SELECT Id,EffectiveDate FROM Orders1__r)
                                                                                                 from MOD_Order_Detail__c where Id=:OrderDetailIds];
       List<MOD_Order_Detail__c> UpdatedOrdDetailList=new List<MOD_Order_Detail__c>();
       Map<Id,List<Order>> OrderMap=new Map<Id,List<Order>>();
       for(MOD_Order_Detail__c ord2 :ordetaillist2)
       {
        OrderMap.put(ord2.Id, new List<Order>{ord2.Orders1__r});
       }      
         for(Order orr:OrderMap.values())
         {
            //dateCalculation2w(orr.EffectiveDate);
            Date ThirdMondayafterStartDate =orr.EffectiveDate.toStartofWeek() + 22 ;
            Date FifthMondayafterStartDate= orr.EffectiveDate.toStartofWeek() + 36 ;
            Date SeventhMondayafterStartDate=orr.EffectiveDate.toStartofWeek() + 50 ;
            Date NinthMondayafterStartDate= orr.EffectiveDate.toStartofWeek() + 64 ;
            Date ThirtneenthMondayafterStartDate= orr.EffectiveDate.toStartofWeek() + 92 ;
            Date SeventeenthMondayafterStartDate= orr.EffectiveDate.toStartofWeek() + 120 ;
            Date TwentyOneMondayafterStartDate= orr.EffectiveDate.toStartofWeek() + 148 ;
            Date TwentyFiveMondayafterStartDate= orr.EffectiveDate.toStartofWeek() + 176 ;
           
            If( orr.EffectiveDate < ord2.MOD_Email_Sent_Date_DR__c && ord2.MOD_Email_Sent_Date_DR__c <= ThirdMondayafterStartDate)
            {
                for (MOD_Order_Detail__c OrdOriginal:ordetaillist)
                {
                    MOD_Order_Detail__c ModOrdDetail=new MOD_Order_Detail__c();
                    ModOrdDetail.MOD_Week__c='2W';
                    ModOrdDetail.ID=OrdOriginal.ID;
                    UpdatedOrdDetailList.add(ModOrdDetail);
                }    
            }
         }
           if(!UpdatedOrdDetailList.isEmpty())
           {
               Update UpdatedOrdDetailList;
           }
      }