How to cover mark Red colour in Test classes

Since i am using trigger after update therefore we should pass as mentioned under :-

Application app = new Application(Status='Submitted',      
                Type__c='new',
               
                Customer__c='5',
                Branch=branch1.id,
                Area = area1.id,
                Meeting = mc.id,
                Loan='42645' ,
                product = Prod.Id 
             
          );
         
          insert app ;
          app .Status = 'Draft';
          update app ;