Hi, my scenario I have 3 objects here. payment term credit limit, sales order and vehicle. let's say when users create new payment term records, the vehicle records will auto-populate based on the sales order. This code is working well for after insert only. but is I put After insert and after update, the vehicle records become double (duplicate value)
 

trigger CreateSOonPtcl on Payment_Term_Credit_Limit__c (after insert, after update) {
    set<Id> lstId = new set<Id>();
    set<date> startDate = New set<date>();
    set<date> endDate = New set<date>();
    List <Vehicle__c> vehToInsert = new List <Vehicle__c>(); 
    
    for (Payment_Term_Credit_Limit__c o : Trigger.new) {
        
        //meets the criteria
        if (o.Category__c == 'Increase / Decrease Credit Limit') {
            lstId.add(o.Name_of_Customer__c);
            startDate.add(o.Start_Order_Date__c);
            endDate.add(o.End_Order_Date__c);
        }
    }
    
    list<Sales_Order__c> lstOb1 =[select Id,Requested_Delivery_Date__c, account__c, Name,Po_No__c,Total_Qty_Pcs__c,Total_Amount_USD__c,Currency__c from Sales_Order__c where Account__c IN :lstId AND Status__c = 'E0005 ZSHP' and Order_Date__c >= :startDate and Order_Date__c <= :endDate order by CreatedDate ];
    for (Payment_Term_Credit_Limit__c oo : Trigger.new) {
        for(integer i=0; i<lstOb1.size(); i++){
            Vehicle__c v = new Vehicle__c ();
            v.Payment_Term_Credit_Limit__c = oo.id;
            V.Sales_Order__c = lstOb1[i].Id; 
            
            vehToInsert.add(v);
        }
    }
    
    try {
        insert vehToInsert;	
    } catch (system.Dmlexception e) {
        system.debug (e);
    }
    
}

please help me with this. I think It is because this code in loop

Vehicle__c v = new Vehicle__c ();