Unable to access remote database from my localhost

I current have a database on my VPS, I am trying to connect to it from my MacBook but unfortunately I am failing.

I have opened port 3306. I have also granted privileges for a user;

GRANT ALL PRIVILEGES
ON myDatabaseName.*
TO ‘root’@'myIP'
IDENTIFIED BY 'Pa55word';

In my database configuration on my MacBook I have the following;

define('DB_NAME', 'myDatabaseName');
define('DB_USER', 'root');
define('DB_PASSWORD', 'Pa55word');
define('DB_HOST', 'vpsIP');

Unfortunately I am still receiving the error;

Error establishing a database connection

Am I doing something wrong?