I've AIBU for traffic.
A couple of months ago, I purchased some fitness classes at my local gym. An invoice was sent to my email and I paid for the classes with my instructor. After the sessions, another invoice was sent over (the instructor had incorrectly billed me) but I paid the invoice anyway and notified her of the error, which she just said she would take off next time. There was absolutely no indication at any point that I had signed up to any type of subscription. It was simply an invoice with the amount for the sessions and then the option to pay for the classes using my bank card. There was no contract, and I didn't sign anything that reflected I had entered into any type of agreement.
Anyway, after two block of sessions with her, I notified her that I wouldn't be continuing as I felt confident to do my own thing. No invoice arrived - but a large chuck of money left my account. I've reached out to her to query this, and her response is that she needs 14 days notice and I must continue with this block of sessions. She didn't tell me I needed to give her notice, and she didn't tell me at any point that it was a subscription I was entering into. I don't have a clue how this has happened tbh. Why send me invoices, and then suddenly no invoice but an automatic withdrawal.
I feel awkward now as I needed that money for DD's birthday and now it's gone and will have to continue with classes that aren't even needed.