@Georgette39 You only have three reviews so any review that is less than 5 will lower your rating. I read the review in question, and your response may have added to the negative impression. It is best to realize that the host response to a review has an audience of potential guests. Being short and professional rather that defensive and accusatory will play better with potential guests. Something like, "It appears that XX misunderstood the listing description and rules. It is our hope that guests will appreciate this attached studio and amenities."
BTW I was not able to determine the studio was attatched either, so perhaps you need to add that to your description and even have an exterior shot showing the proximity of the studio to your home. You can spin that proximity in a positive manner such as emphasizing your availability to quickly respond to concerns or questions.