Custom Email Notifications Template Ignored

Expected behaviour
Send an email notification when a file is deleted. I want like this example:

Hello User,

You are receiving this email because the following things happened at http://owncloud-files(...)/

  • User1 deleted TESTE/2017/Teste1.xls - Today at 3:15:41 PM
  • User2 deleted TESTE/2017/Teste2.xls - Today at 3:20:41 PM

Actual behaviour
Iam having an issue with ownCloud and its notification emails. The emails are working (although I'm somewhat confused as to its randomness). I have made a few modifications as the admin user in the Email templates in the Admin section of ownCloud. i have also restarted the webserver to make sure owncloud picks up any changes. Is this a bug or is there somewhere further I can look?

Server configuration
Operating system: CentOS Linux release 7.2.1511 (Core)
Web server: Apache/2.4.6 (CentOS)
Database: mysql Ver 15.1 Distrib 5.5.50-MariaDB, for Linux (x86_64) using readline 5.1
PHP version: PHP 5.4.16
ownCloud version (see ownCloud admin page): ownCloud 9.0.5 (stable)
Updated from an older ownCloud or fresh install: fresh install
Special configuration (external storage, external authentication, reverse proxy, server-side-encryption):

Integrity status for oC9+

No errors have been found.

From the issue template you have filled out:

Before posting please snip make sure that you're running the latest available version for your oC release:

9.0.5 is outdated and might contain bugs causing such issues. To avoid that you're reporting issues and causing effort for users helping here, please always use a current version like 9.0.8 or 9.1.4. This makes sure that you're not reporting issues already fixed in newer versions.