I have a trigger that updates the contact owner to whoever the account owner is when the account owner is changed.  I also need the trigger to allow for account teams and dataloading the account owner changes.  Trigger works on a 1 for 1 basis but still has 0% coverage and test class fails.  Any help is really greatly appreciated.

Trigger:
trigger reassignContactOwnerToAccountOwner on Contact ( after insert ) {

    List<Id> accountIds = new List<Id>();
    Map<Id, Id> accountOwnerIdMap = new Map<Id, Id>();

    // all the accounts whose owner ids to look up
    for ( Contact c : Trigger.new ) {
        accountIds.add( c.accountId );
    }
    
    // look up each account owner id
    for ( Account acct : [ SELECT id, ownerId FROM account WHERE id IN :accountIds ] ) {
        accountOwnerIdMap.put( acct.id, acct.ownerId );
    }
    
    // change contact owner to its account owner
    for ( Contact c : Trigger.new ) {
        c.ownerId = accountOwnerIdMap.get( c.accountId );
    }
   
}

Test Class:
@IsTest
private class AccountContactOwner {
    static TestMethod void testTrigger()
    { 
        test.StartTest();
        
        //Step 1 : Data Insertion
        Account a=new Account(Name='Test Account');
           insert a;
           Contact c = new Contact(Account=a, FirstName='John',LastName='Doe');
        update c;
        
        
        test.startTest();
        
        
        //Perform the dml action on which trigger gets fired , like insert, update ,delete , undelete, in your case you have to update account record that you created in above  
        //create test user
            Profile p = [SELECT Id FROM Profile WHERE Name='Standard User'];
      User u1 = new User(Alias = 'standa', Email='saplingstandarduser@testorg.com',
      EmailEncodingKey='UTF-8', LastName='Testing', LanguageLocaleKey='en_US',
      LocaleSidKey='en_US', ProfileId = p.Id,
      TimeZoneSidKey='America/Los_Angeles', UserName='saplingstandarduser@testorg.com');


      System.runAs(u1) {
      // The following code runs as user 'u'  
       // create test contact
        Contact c1 = new Contact(FirstName='Jane',LastName='Doe', Account=a);
        insert c1;
        
        //assert your results using system.assert and system.asserEquals

//reload objects to make sure values are loaded
   a= [select id, ownerId from Account where id=:a.id];
                
        
        
        test.stopTest();
    }
}
}