N.Y. Comp. Codes R. & Regs. tit. 10, § 1004.19
(i) If a certified patient wishes to change or terminate his or her designated caregiver, the certified patient shall notify the department, in a manner determined by the department, and shall notify his or her designated caregiver as soon as practicable.
(j) If a designated caregiver wishes to terminate his or her relationship with a certified patient, the designated caregiver shall notify the department, in a manner determined by the department, and shall notify the certified patient, as soon as practicable.