protected virtual string GetContactNumber(Customer customer)
 {
     if(customer==null)
     {
         return null;
     }
     return customer.Identity.ContNumber;
 }
 protected virtual string GetEmail(Customer customer)
 {
     if (customer == null)
     {
         return null;
     }
     return customer.Identity.EmailID;
 }
 public abstract void SendNotification(Customer customer,string notificationMessage );