Myosotis interview questions

Personal contact via LinkedIn, then a call, and then they asked for a design challenge. The challenge was exactly, what they planned to design and implement next for the product. They provided me a design style guide etc. internal materials, and asked me to provided them SKETCH -files of the design. Before sending anything, i asked how they are going to use my designs (because the challenge was exactly what were going to do next). They just said "Just finish it by sunday and than we can talk about an appointment on monday evening. " I asked again for how they are using the design challenge results, and the next answer was "Can you send me your results. I will forward them to Jasper and he will then come back to you." I sent my design as pdf, marked (c) as copyright on top of all the pictures. They never came back to me. I'm sure this is a hoax, and I am assuming they are using the design challenge results as free design work for their product.