For immediate assistance during normal business hours, Huntington Debt Holding’s expert representatives can be contacted toll-free at 888-326-1253. Our business hours are Monday through Friday: 9am to 5pm EST. You may also email our team at customersupport@hdhllc.net or by sending mail to Huntington Debt Holding, 1965 Sheridan Dr, Suite 200, Buffalo, NY, 14223.