Service canceled and still receiving bill

I’ve canceled my service on the same day it was installed because the At&t representative that sold me the service said we’d have fiber optic service, and after everything was installed I realized (installation technician told me) that fiber is not available on my street. At&t told me I wouldn’t have any charges, zero charges when I cancelled the service by phone. And now I’m receiving a bill ! Also, all my equipments were returned, I have an e-mail “confirmation of equipment return”, and At&t is charging me for one of the equipments.