global class updatesaccount implements 
    Database.Batchable<sObject>, Database.Stateful
{
    global Integer recordsProcessed = 0;

   global Database.QueryLocator start(Database.BatchableContext bc) {
        return Database.getQueryLocator(
            'SELECT ID, Phone, ' +
            'Fax, (SELECT ID, Phone, ' +
            'Fax FROM Contacts) FROM Account ' + 
            'Where Industry = \'Construction\''
        );
    }

    global void execute(Database.BatchableContext bc, List<Account> scope ){
        
      List<Contact> contacts = new List<Contact>();
        for (Account account : scope) {
            for (Contact contact : account.contacts) {
                contact.Phone = account.Phone;
                contact.Fax = account.Fax;
             
               
                
                contacts.add(contact);
               
                recordsProcessed = recordsProcessed + 1;
            }
        }
        update contacts;
    }    

    global void finish(Database.BatchableContext bc){
        System.debug(recordsProcessed + ' records processed. pradeepvarma');
        AsyncApexJob job = [SELECT Id, Status, NumberOfErrors, 
            JobItemsProcessed,
            TotalJobItems, CreatedBy.Email
            FROM AsyncApexJob
            WHERE Id = :bc.getJobId()];
       
        Messaging.SingleEmailMessage mail = new Messaging.SingleEmailMessage();
          String[] toAddresses = new String[] {'pradeep.gunturi@gmail.com'};
               mail.setSubject('Match Merge Batch ');
            mail.setPlainTextBody('hi pradeep batchapex completed');
         mail.setToAddresses(toAddresses);
       List<Messaging.SendEmailResult> sendRes = Messaging.sendEmail(new Messaging.SingleEmailMessage[] { mail }, true);
        
       
    }    

}


i want copy phone and fax of account whos industry is construction

but when ever we create new contact its sshowing whats problem in prgrm