Negative reviews aren't necessarily a sign of bad business practices. For example, the customer may have had mismatched expectations. Reviews can also help identify points on how to improve future customer experiences.
Here are some best practices from Google to keep in mind:
Do not share personal data of the reviewer or attack them personally. This includes on Maps, on other services, or in the real world. Instead, suggest that they contact you personally by email or phone to resolve the issue. A positive post-review interaction and your reply shows prospective shoppers that you really care and often leads the customer to update their original review.
Investigate the reasons behind the reviewer’s negative impression of the business. Check your records for the reviewer and their experience with your business.
Be honest. Acknowledge mistakes that were made, but don’t take responsibility for things that are out of your control. Explain what you can and can't do in the situation. Show how you can make uncontrollable issues actionable. For example, bad weather caused you to cancel an event, but you monitor the weather and provide advance cancellation warnings when possible.
Apologize when appropriate. It’s best to say something that demonstrates compassion and empathy.
Show that you’re a real person by signing off with your name or initials. This helps you come across as more authentic.
Respond in a timely manner. Doing so shows that you pay attention to your customer’s experience.