I reserved a hotel room with my card the hotel said it would charge 50% deposit but charged 100% I did sign the agreement.

I reserved a hotel room with my credit card, then I cancelled the reservation. The hotel policy written on the agreement is to charge 50% for cancellations, however, they charged my card 100% of the stay. I did sign the agreement where they just wrote in figures which totaled the 100% of the stay. I cancelled the credit card charges right away but now I am being force to pay $1400.00 and I didn't stay in the hotel for one night.