@Sapna11 Sorry she held you responsible for something out of your control. As Helen advised, a brief, factual response, directed towards future guests is in order.
However, just because your previous guests weren't bothered by any noise from the neighbors, doesn't mean it might not be an issue in the future. So it would be wise to determine if this was just a one-off of the neighbors being noisy one evening, or whether it's something that happens a lot. You might have to go stay there yourself for a night or two to know this. If they are just loud in general, it would be smart to at least mention the "potential for noise" under "Other things to note" in your listing, and explain what that noise is, be it traffic, neighbors or barking dogs.
Mentioning the possible negatives associated with any listing is a good idea, so guests are forewarned. Many hosts only write up their listings making it all sound totally wonderful, thinking if they mention noise, or anything else negative, it will stop them from getting bookings. But it will only stop you from getting bookings from guests who would find those things a deal-breaker, and you don't want those guests anyway, as they'd leave a bad review because of it. And if you mention it in the listing, a guest can't claim they didn't know what to expect.