Hello, I've created a trigger in order to create a case when a new product is added to an opportunity, according some rules.

But now, for a product added case is created more then once.

This is the trigger:

trigger NewProductAdded on OpportunityLineItem (after insert) {

//Query for Case record types
     List<RecordType> rtypes = [Select Name, Id From RecordType where sObjectType='Case' and isActive=true];
     
//Create a map between the Record Type Name and Id for easy retrieval
     Map<String,String> CampaignsRecordTypes = new Map<String,String>{};
     for(RecordType rt: rtypes)
     CampaignsRecordTypes.put(rt.Name,rt.Id);
     
//Query for Users 

    List<User> users = [Select Name, Id From User];
    
//Create a map between the User Name and Id for easy retrieval

     Map<String,String> CaseUsers = new Map<String,String>{};
     for(User  usr: Users)
     CaseUsers.put(usr.Name,usr.Id);
     
for (OpportunityLineItem oli : Trigger.new) 
 { 
     if (oli.Implementation_DirectTrack__c == 'Yes'& (oli.Approval_status__c == 'Approved by AD'))
        
    { 
       Case c = new Case ( 
       Opportunity__c = oli.OpportunityId, 
       Status = 'New', 
       Origin = 'Web', 
       Type = 'Internal Case', 
       Reason = 'Add Campaign to R-ADserver', 
       Description = 'Hello, a new product has been added. Please add campaign to R-Adserver',
       R_Adserver_Status__c = '',
       RecordTypeId=CampaignsRecordTypes.get('Traffic'),
       Account_Manager__c = oli.Account_Manager__c,
       OwnerId = CaseUsers.get('Traffic List') 
       ); 
       insert c; 
    }   
     else if (oli.Implementation_DirectTrack__c == 'No' & (oli.Approval_status__c == 'Approved by AD') )
    { 
       Case c = new Case ( 
       Opportunity__c = oli.OpportunityId, 
       Status = 'New', 
       Origin = 'Web', 
       Type = 'Internal Case', 
       Reason = 'Add Campaign to Emediate', 
       Description = 'Hello, a new product has been added. Please add campaign to Emediate',
       RecordTypeId=CampaignsRecordTypes.get('Traffic'),
              Account_Manager__c = oli.Account_Manager__c,
       OwnerId = CaseUsers.get('Traffic List')  
       ); 
       insert c; 
    } 
    else { } 
 }         

}

Any idea about how to fix it?

Many thanks in advance,

Stefano Di Leone