If the patient portal is unavailable, please phone our office and select option 2 from the greeting. ... Doctor Robert L. Benak, MD, Internal Medicine. Certified Nurse Practitioners Lynn E. Schneider, ANP-C Carla K. Hausrath, ANP-C . Contact Us 459 Margaret St. Plattsburgh, NY 12901 . Phone # 518-563-6348 Fax # 518-563-6378. Office Hours..