Ugh, that's rough but I gotta say, those trials are usually free. You might have accidentally signed up for a full week instead of the trial. Check if they charged you for the first box, because that's how they get you.
Read an article last year about how these companies make the trial sign-up page confusing on purpose. The "free trial" button is often tiny, while the paid option looks like the main choice. @the_sage is right about checking for that first charge, it's basically their business model. They bank on people forgetting to cancel during the trial window. Always set a phone reminder for the cancellation date right after you sign up.
That's actually so shady if they design the page to trick you. Makes me wonder if that's even legal, hiding the real free option like that. Setting a reminder is smart, but it feels wrong that we have to play defense just to use a trial. What's the worst one you've seen for tricky sign-ups?