code: public Contact updateContact(final String id, ContactRequest contactRequest) throws UnauthorizedException, GeneralException {
          if (id == null) {
              throw new IllegalArgumentException("Contact ID must be specified.");
          }
          String request = CONTACTPATH + "/" + id;
          return messageBirdService.sendPayLoad("PATCH", request, contactRequest, Contact.class);
      }
docs: Updates an existing contact. You only need to supply the unique id that
  was returned upon creation.