I’m a self-employed consultant working at home in CT. A client in DE issued me a 1099. I'm not an employee. Do I need to file a non-resident state return in DE?

I've read conflicting information. If I was an employee of the firm I know I would have to file, but it's not clear to me if it's something I need to do as a contractor based in CT, employed by me in CT, who never goes to their office in Delaware.