code: public void unsubscribe(final String tagName,
    final MFPPushResponseListener<String> listener) {
      if (isAbleToSubscribe()) {
        MFPPushUrlBuilder builder = new MFPPushUrlBuilder(applicationId);
        String path = builder.getSubscriptionsUrl(deviceId, tagName);
  
        if (path == DEVICE_ID_NULL) {
          listener.onFailure(new MFPPushException("The device is not registered yet. Please register device before calling subscriptions API"));
          return;
        }
  
        logger.debug("MFPPush:unsubscribe() - The tag unsubscription path is: " + path);
        MFPPushInvoker invoker = MFPPushInvoker.newInstance(appContext, path, Request.DELETE, clientSecret);
  
        invoker.setResponseListener(new ResponseListener() {
          @Override
          public void onSuccess(Response response) {
            logger.info("MFPPush:unsubscribe() - Tag unsubscription successful.  The response is: " + response.toString());
            listener.onSuccess(tagName);
          }
  
          @Override
          public void onFailure(Response response, Throwable throwable, JSONObject jsonObject) {
            //Error while Unsubscribing to tags.
            logger.error("MFPPush: Error while Unsubscribing to tags");
            listener.onFailure(getException(response,throwable,jsonObject));
          }
        });
        invoker.execute();
      }
    }
docs: Unsubscribes to the given tag
  
  @param tagName  name of the tag
  @param listener Mandatory listener class. When the subscription is deleted
  successfully the {@link MFPPushResponseListener}.onSuccess
  method is called with the tagName for which subscription is
  deleted. {@link MFPPushResponseListener}.onFailure method is
  called otherwise