Is there anything she can do?

My sister has just had a photoshoot. The company said, in their leaflet, there was no obligation to buy the photos, but you would not take part in the other section of the photo shoot. My sister got duped into getting the photos, and signed a contract. However she has now realised she cant afford to pay the monthly payments. The contract states its non cancelable. But the part of the form with her details my sister didnt fill in. The women in charge of the photoshoot did and my sister just signed it with out reading it.The contract states that my sister can afford the payments, and the women who filled it in also ticked that my sister has a anual income of �10,000, which my sister does not. Is there anything my sister can do? As she isnt going to be able to pay the payments and is she only 18.