Dear all,

I have created a trigger in my Sandbox which automatically submits an Opportunity to an approval process once the Stage is changed to either 'Won' or 'Lost'. I have attached both code snippets below.

It is now working fine in my sandbox but when I try to deploy it to the production Org I receive the following error on the test class referring to the last line of code of the test class.

Many thanks for any support!

trigger OpportunitySubmitForOrderListApproval on Opportunity (after update) {
 
    for(Integer i = 0; i < Trigger.new.size(); i++) 
    
     {
        if ((Trigger.old[i].StageName <> '6 - Project won'  ||  Trigger.old[i].StageName <> '7 - Project lost')  && (Trigger.new[i].StageName == '6 - Project won'  ||  Trigger.new[i].StageName == '7 - Project lost')) 
        {
 
            Approval.ProcessSubmitRequest req = new Approval.ProcessSubmitRequest();
            req.setComments('Submitted for approval. Please approve.');
            req.setObjectId(Trigger.new[i].Id);
            Approval.ProcessResult result = Approval.process(req);
            System.assert(result.isSuccess());  
 
        }
       
    }
 }

@isTest
private class TestOpportunitySubmitForOrderApproval {
 
    static testMethod void testApprovalSuccess() {
 
        Opportunity opp = new Opportunity();
        opp.Name = 'Test Opp';
        opp.Amount = 100;
        opp.CloseDate = Date.today();
        opp.StageName = '0 - New Opportunity';
        opp.Division__c= 'SYS';
        // insert the new opp
        insert opp;
        // change the probability of the opp so the trigger submits it for approval
    opp.StageName = '6 - Project won';
    // update the opp which should submit it for approval
    update opp;
 
        // ensure that the opp was submitted for approval
        List<ProcessInstance> processInstances = [select Id, Status from ProcessInstance where TargetObjectId = :opp.id];
    System.assertEquals(processInstances.size(),1);
 
    }
 }