Wipe Data from old iPhone that has a black screen

My old iPhone was replaced by the company and I need to send it back to Apple, with the data wiped clean. I have tried through iTunes but old device never set up with that program, as with Find my iPhone and I'm feeling pretty hopeless as each other avenue I have taken, seems to get me right back where I started. Can I take it to a MacEdge or Apple store to have them do it?