Fetching all data from product record and creating new material records using the same information but i want  a confirmation dialog box if new material with same name is already exit in material object record. I tried code below but it is unable to check duplicate record in material.When i clicked "createMaterial" button,everytime it is created material record using product record data. Could you please see the code and let me know what i am missing. I thought that duplicate logic is not able to call.

APEX CLASS:

Public class ctrlCloneProductToMaterial{
        Public Id id;
        public List<Material__c> dupe;
        public boolean dupFound{get; set; }
        public static final Id Material_Rtype=Rtype.getIdByDevName('material__c','DEC');
        public static final Id Product_Rtype=Rtype.getIdByDevName('product2','DEC');

        public ctrlctrlCloneProductToMaterial(apexPage.StandardController contoller){
           id=apexPages.currentPage().getparameters().get('id');
          }
        
       public PageReference cloneProduct(){
           product2 prod=new product2();
           Material__c mat= new Material__c();
            prod=[select name,Id,Description,Productcode from Product2 where Id=:id and Recordtypeid=:Product_Rtype]   
        
           dupe=[select Name,id from material__c where Name=:prod.Name];
           if(dupe.size()>0){
           dupFound= true;
            }
          else{
             mat=new material__c(Name=prod.name,Description__c=prod.Description);
             insert mat;
             Id matid=mat.id;
             return new pageReference('/'+matid);  
         }       
        }
}

APEX PAGE:

<apex:page Standardcontroller="product2" extension="ctrlCloneProductToMaterial">
<script type="text/javascript">
function alertMessage(){
   if ({!dupFound}== 'true'){
      var r = confirm ("existing material Do u want to continue");
       if(r== true){
              clone();
              alert('product cloned');          
             }  
        else{
             // return back to detail page of product record
              } 
     }
else{
              clone();
              alert('product cloned')   
       }
}
</script>

<apex:form>
<apex:acctionFunction action="{!cloneProduct}" name="clone" oncomplete="alertmessage()"/>
</apex:form>
</apex:page>