Who pays taxes on a mobile home paid before purchase?

[Gina Lisco]

We purchased a mobile home with land in Oswego N.Y. on October 6th 2020. The seller paid his taxes on October 4th 2020, before we bought the place. We’ve been trying to transfer the deed since we moved in. The seller will not return our calls or answer any of our texts but did send us a letter asking us to pay him for the taxes he paid and he will forward the deed then. He paid the taxes before we bought the place. What can we do to get the deed?