N.Y. General Obligations Law § 15-304
2. If any lessee, or its assignee fails to cancel a lease, as provided for in subdivision one of this section, the current owner of the land which is subject to the lease may:
(a) serve notice upon the lessee, and if actual or record notice of their identity exists, to its assignee, that such lease be cancelled as of record, and stating that if such release is not executed within thirty days of the service of such notice, the lease will be terminated and no longer of any effect. Such notice shall also state;