As a general matter, deposits are non-refundable unless--1) the business failed to provide the services or goods contracted for (that is, if the reason she wanted to cancel is that you could not provide her services on the date you were supposed to  or else that *you* did something wrong); or2) the contract says that deposits are refundable under certain circumstances, and those circumstances apply.On the other hand, if with no fault of yours and no language or agreement that the deposit is refundable, she simply changed her mind, you would normally be allowed to keep the deposit.