Do you have to receive a final notice before debt collectors can be involved?

I've been sent letters about my debt, but not one was a final notice...

Do they need to send a final notice before contacting debt collection agencies?

It's a college regarding course fees.

What is a VPN?

VPN is (Virtual Private Network) were first used by companies to enable their employees to securely access internal systems such as email remotely (e.g. from home or while on business trips). Today they are increasingly being used for personal use by individuals to protect their privacy while online in public places (e.g. when using the wi-fi connection in a cafe) or in a country where the internet is censored / blocked (e.g. China, Saudi Arabia…).