breach of contract

Why did the photographer offer you a full refund?  There's nothing in your question to indicate that she had any obligation to do so. Neverthelless, if there was consideration for this promise, i.e. the photographer got something in return (including being let off the hook for any services she had yet to render), and the photographer didn't condition her offer to you on anything (like "if I can book another gig on that date I'll give you a full refund) it is a valid contract (absent other things which you do not mention, like if she is a minor, or was coerced or defrauded into offering the refund).  You have the right to the full refund. One caveat.  From your question I have assumed that you contracted with the person who offered you the refund.  If you contracted with another person or entity, which could happen even if the photographer offering the refund signed the contract (for example, if she signed for XYZ Photos, or for her father), that person or entity may claim that she had no authority to offer a refund.  However, if the photographer offering the refund signed the contract, any lack of authority argument is likely doomed; if she had authority to enter into the contract, she had apparent authority to offer the refund.