if found duplicates records based on customer number field unique,so update to exiting record and new record need to delete?please help me on this

trigger GE_LGT_EM_AvoidDuplicateAccount on Account (before insert,before update) {

    Map<String, Account> AccountMap = new Map<String, Account>();
    set<string> deleteAccountMap = new set<string>();
    Map<id,account>updateacc=new Map<id,Account>();
    List<recordtype> rt=[select id,name from recordtype where sobjecttype='Account' and name='EMEA Account'];
        for (Account acc :System.Trigger.new)
        {
        if ((acc.GE_LGT_EM_SAP_Customer_Number__c != null) && acc.RecordTypeid==rt[0].id && (System.Trigger.isInsert ))
        AccountMap.put(acc.GE_LGT_EM_SAP_Customer_Number__c, acc);
         deleteAccountMap.add(acc.id);
        }
      
    list<account> acclist=[SELECT id,
    Name,
    GE_LGT_EM_Partner_Function__c,
    BillingStreet,
    BillingCity,
    BillingState,
    BillingPostalCode,
    GE_LGT_EM_CustomerActiveFlag__c,
    GE_LGT_EM_Tax_Number_1__c,
    GE_LGT_EM_Tax_Number_2__c,
    CurrencyIsoCode,
    GE_LGT_EM_Plant__c,
    GE_LGT_EM_PF_Type__c,
    GE_LGT_EM_SAP_Customer_Number__c FROM Account WHERE RecordTypeid=:rt[0].id and GE_LGT_EM_SAP_Customer_Number__c IN:AccountMap.KeySet()];
        system.debug('-------->acclist'+acclist);
        for(Account c :Trigger.new)
        {
            for(Account acct:acclist)
           {
           system.debug('----------->inside for loop');
               if(c.GE_LGT_EM_SAP_Customer_Number__c==acct.GE_LGT_EM_SAP_Customer_Number__c && AccountMap.containsKey(c.GE_LGT_EM_SAP_Customer_Number__c) && c.RecordTypeid==rt[0].id)
                {
                    acct.Name=c.Name;
                    acct.GE_LGT_EM_Partner_Function__c=c.GE_LGT_EM_Partner_Function__c;
                    acct.BillingStreet=c.BillingStreet;
                    acct.BillingCity=c.BillingCity;
                    acct.BillingState=c.BillingState;
                    acct.BillingPostalCode=c.BillingPostalCode;
                    acct.GE_LGT_EM_CustomerActiveFlag__c=c.GE_LGT_EM_CustomerActiveFlag__c;
                    acct.GE_LGT_EM_Tax_Number_1__c=c.GE_LGT_EM_Tax_Number_1__c;
                    acct.GE_LGT_EM_Tax_Number_2__c=c.GE_LGT_EM_Tax_Number_2__c;
                    acct.CurrencyIsoCode=c.CurrencyIsoCode;
                    acct.GE_LGT_EM_Plant__c=c.GE_LGT_EM_Plant__c;
                    acct.GE_LGT_EM_PF_Type__c=c.GE_LGT_EM_PF_Type__c;
                    updateacc.put(acct.id,acct);
                }
                        
            }      
        }
   
   if(updateacc.size()>0){
     system.debug('----------->update final');
   update updateacc.values();
   }
  
  /**************delete duplicate account**************/
   set<string> uniqueIds = new set<string>();

    for (Account s : Trigger.new)
        uniqueIds.add(s.GE_LGT_EM_SAP_Customer_Number__c);

    list<Account> existingAccounts = [select id,GE_LGT_EM_SAP_Customer_Number__c from Account where GE_LGT_EM_SAP_Customer_Number__c in :uniqueIds and RecordTypeid=:rt[0].id];

    list<Account> dupestodelete = new list<Account>();
    for (Account s : Trigger.new)
    {
        for (Account existing : existingAccounts)
        {
            if (s.GE_LGT_EM_SAP_Customer_Number__c == existing.GE_LGT_EM_SAP_Customer_Number__c )
            {
                dupestodelete.add(s);
                continue;
            }
        }
    }

    delete dupestodelete;

}