how to properly bind a database to be used in app?

Hi! I’m experiencing the app platform to deploy a single WordPress application. So, I created a database to be associated with the app and I did the deploy but I can’t connect the WordPress application with the database. I followed all the connection instructions.

The app contains two components: the web service and the database.

The app inspec:

databases:
- cluster_name: db-mysql-mikhael
  db_name: wordpress_rpodonto
  db_user: rpodonto
  engine: MYSQL
  name: db-mysql-mikhael
  production: true
  version: "8"
domains:
- domain: www.rpodonto.com.br
  type: PRIMARY
name: wordpress-rpodonto
region: nyc
services:
- environment_slug: php
  envs:
  - key: DATABASE_URL
    scope: RUN_TIME
    value: ${db-mysql-mikhael.DATABASE_URL}
  github:
    branch: master
    deploy_on_push: true
    repo: mikhaelangelo/wordpress_rpodonto
  http_port: 8080
  instance_count: 1
  instance_size_slug: basic-xxs
  name: wordpress-rpodonto
  routes:
  - path: /
  run_command: heroku-php-apache2

notice the env variable “DATABSE_URL” which contains the URL seted by the “wizard” database setup.

What i’m doing wrong?