I got below error
"update failed  Cannot_insert_update_activate_entity samplelotprocess: execution of afterupdate caused by ssytem dmlexception :update failed" 

i noticed error shows in line no 82 at the time of update any idea why please advise me


trigger SampleLotProcess on Sample_Lot__c (after insert, after update) {
    class SampleLotProcessHandler {
        Sample_Lot__c[] oldRows;
        Sample_Lot__c[] newRows;
        Map<Id, Sample_Lot__c> oldMap;
        Map<Id, Sample_Lot__c> newMap;
        
    Map<String, RecordType> rtMap;
        
        
        public void initialize(Sample_Lot__c[] oldRows, Sample_Lot__c[] newRows, Map<Id, Sample_Lot__c> oldMap, Map<Id, Sample_Lot__c> newMap) {
            this.oldRows = oldRows;
            this.newRows = newRows;
            this.oldMap = oldMap;
            this.newMap = newMap;
           
        }

        public void onAfterInsert() {
            createReceipts();
        }
        
        public void onAfterUpdate() {
            createReceipts();
        }   
        
        public void createReceipts() {
            Sample_Lot__c[] filteredRows = new Sample_Lot__c[0];
            Set<Id> transferIds = new Set<Id>();
            for (Sample_Lot__c item : newRows) {
                if (item.Status__c != 'Confirmed') continue;
                if (oldMap != null && item.Status__c == oldMap.get(item.Id).Status__c) continue;
                
                filteredRows.add(item);
                if (item.Original_Transfer_Transaction__c != null) {
                  transferIds.add(item.Original_Transfer_Transaction__c);
                }
            }            
            
            Sample_Transaction__c[] transfers = [select id, Status__c, Transferred_From__c  from Sample_Transaction__c where id in :transferIds];
            Map<Id, Sample_Transaction__c> transferMap;
            if (transfers.isEmpty()) {
                transferMap = new Map<Id, Sample_Transaction__c>();
            } else {
                transferMap = new Map<Id, Sample_Transaction__c>(transfers);
            }
            
            Sample_Transaction__c[] forIns = new Sample_Transaction__c[0];
            
            for (Sample_Lot__c item : filteredRows) {
                if (item.Status__c != 'Confirmed') continue;
                if (oldMap != null && item.Status__c == oldMap.get(item.Id).Status__c) continue;
                
                Sample_Transaction__c newReceipt = new Sample_Transaction__c();
                newReceipt.Transfer_To__c = item.OwnerId;
                newReceipt.Comments__c = item.Comments__c;
                newReceipt.Quantity__c = item.Confirmed_Quantity__c;
                newReceipt.OwnerId = item.OwnerId;
                newReceipt.Transfer_To__c = item.OwnerId;
                
                if (transferMap.containsKey(item.Original_Transfer_Transaction__c)) {
                    newReceipt.Transferred_From__c = transferMap.get(item.Original_Transfer_Transaction__c).Transferred_From__c;
                    transferMap.get(item.Original_Transfer_Transaction__c).Status__c = 'Confirmed';
                }
                
                if (getRtMap().containsKey('Reckitt_Receipt')) {
                    newReceipt.RecordTypeId = getRtMap().get('Reckitt_Receipt').Id;
                }     
                
                newReceipt.Product__c = item.Product_ID__c;
                newReceipt.Sample_Lot_ID__c = item.Id;
                newReceipt.Transaction_Date__c = Date.today();
                
                forIns.add(newReceipt);
            }
            
            if (!forIns.isEmpty()) {
                insert forIns;
            }
            
            if (!transferMap.isEmpty()) {
                update transferMap.values();
            }
        }
        
        public Map<String, RecordType> getRtMap() {
            if (rtMap == null) {
                rtMap = new Map<String, RecordType>();
                
                RecordType[] rtList = [select id, DeveloperName from RecordType where SObjectType = 'Sample_Transaction__c'];
                
                for (RecordType item : rtList) {
                    rtMap.put(item.DeveloperName, item);
                }
            }
            
            return rtMap;
        }
    }
    
    SampleLotProcessHandler handler = new SampleLotProcessHandler();
    handler.initialize(trigger.old, trigger.new, trigger.oldMap, trigger.newMap);
    
    if (trigger.isAfter && trigger.isInsert) {
        handler.onAfterInsert();
    } else if (trigger.isAfter && trigger.isUpdate) {
        handler.onAfterUpdate();
    }
}