If the review was left by an unhappy customer, call them and find out what you can do to resolve the issue. If you don't know who left the review, you may be able to log in and reply to it. Never argue or leave a rude reply no matter how unpleasant the review might be. In some cases, you may be able to have the review website remove the review. For details about customer reviews, how to avoid them, how to respond to them, and more, read my blog on how to handle negative customer reviews.