Performed a 2 nd floor dryer from the inside using brushes and nikro vac. Unable to locate vent. It appears to flow into the soffit. Duct, flex hose and lint trap are all clear of lint and debris at this time . Performed first floor dryer vent cleaning. Dryer vent duct and flex hose are free of lint and debris at this time. Both dryers are functioning properly at this time. Recommend dryer vent cleaning every 1-2 years. Thank you for business!