I subscribed to a porn site a while back, I went to cancel it but the lady says the number changed?

I called the exact number charged on my account however the lady who answered said my member account was not pulling up and that i was not on the database. she said I would have to consult my bank to inquire about the correct number to which im supposed to call. This all sounds shady to me and i wish i never signed up, I want to cancel asap but I dont know how to start please help!