Setting Up Email Configuration

When attempting to configure the email for forgotten passwords, the emails don't send at all.

I have followed this set up directly. https://docs.grabaperch.com/perch/configuration/email/

I am pretty sure the problem does not lay with the host provider, as the contact form which is embedded into the website works fine.

I have tried changing the port numbers in accordance with googles support. https://support.google.com/a/answer/176600?hl=en

But every time I test the email via the settings, it just times out. 504 Gateway Error.

define('PERCH_EMAIL_FROM', 'CorrectEmail');

define('PERCH_EMAIL_FROM_NAME', 'Name');

define('PERCH_EMAIL_METHOD', 'smtp');

define('PERCH_EMAIL_HOST', 'smtp.gmail.com');

define('PERCH_EMAIL_AUTH', true);

define('PERCH_EMAIL_SECURE', 'ssl');

define('PERCH_EMAIL_PORT', 25);

define('PERCH_EMAIL_USERNAME', 'CorrectEmail');

define('PERCH_EMAIL_PASSWORD', 'CorrectPassword');

Is there anyway to debug this issue?

Many thanks.