Hi Clifford, do you mean a subscription to an email newsletter? There should be a link in the email to unsubscribe.

If you mean a different kind of subscription, could you describe it in more detail?

Don't I have to pay for Mizilla Firefox after my trial period is over?

No. Maybe.

Firefox is 100% free, you don't even need to give any contact information to use it. If you gave someone your credit card number or any other way to charge you, unfortunately, you were scammed and you need to take action to stop it.

Real Firefox download site: https://www.mozilla.org/firefox/