Unauthorized debit transaction from my account

I booked a hotel room through stayforlong which is a travel agency for the hotel. I paid online and they reversed the payment with the reason that they are fully booked. I went ahead and booked another accommodation. This morning I get a bank notification saying that Stayforlong has deducted money from my account without my consent for the same booking that they canceled I have been calling and emailing them without luck of any assistance to get my money back.