To cut the story short, I canceled my subscription and they decided to use my credit card details to take all the money from my account. I can't get hold of them, and I can't reverse the transaction. It's a devastating situation for me.
Please, please run while you still can and change your banking details before you end up like me.
You didn't provide many details, but if you signed up to a yearly contract then you were given a discounted monthly price, so if you then cancel that contract before the year is up you're required to pay the difference between the discounted amount you paid and the actual cost of a monthly subscription. This is hardly a "scam" and is specified in the T&C of the contract you signed (but maybe didn't read properly).
Ok, so if you cancel, you get to pay for the whole year but the subsrcibtion is terminated immidiately.
I get it when you say it's not a scam, you just capitalizing on those customers who don't read your fine print.
It's useful to know that you can't escape debt or promises to pay or contract terms, by changing bank details or cancelling cards. Instead things can get MUCH worse, especially if your debt is sold to a recovery agency. Companies expect you to keep your promises and the law is on their side.