Hyatt review: unauthorized credit card charges

My name is Cecilia Gonzalez Blanco. I was staying at The Hyatt Hotel Rio de Janeiro from nov the 24th to nov the 28th with all my sisters and we rented two bedrooms.
During our departure day I realized the hotel had charged me USD976.08 to my VISA by mistake and Thais Monteiro, from the Accountant department, promised me to cancel the expense in the next days.
On Friday I called the hotel and I got Thais email and yesterday I sent her an email with my request, but I didn't get any answer.
Can you please help me to resolve this issue?
I need my money back asap.