The townhall keeps records of all properties, I would check those records as a primary check point.
However, the townhall is not 100% accurate, so it very well may be that there is a mistake in the records. Your survey is a good way to back up the claim and have it changed.
We have several people in our network who can assist you with this change. If you wish, please call me and I will be happy to help
Equity Capital Real Estate
(203) 280 3838