I bought this black eye for my iPhone and the instructions are very simple: Place the lens on the camera. I did so and and I see is a blurry display through my phone. I put the sense on properly without any dust and it is entered properly. Is this a defective product or am I doing something wrong?
A diopter lens* like this is really only supposed to work at VERY close distances, which your unmodified phone or camera lens won't focus to (otherwise, there is no need to use a diopter). From the picture, it looks like you are holding the camera a two feet or more away from the subject - the phone can likely focus on that just fine without a diopter. Try using it on a subject just an inch away - that is what the specifications say, "20-26mm focus distance".
If you need magnification of a far away subject instead of close ups of something very near, you need to shop for a "telephoto", not "macro" accessory.
This accessory enables "microscope", not "telescope" behaviour.
*This would be the precise term to a photographer. "Macro lens" is ambigous, it could mean a diopter attachment for either a phone or camera, but a camera store would assume you want to buy a complete interchangeable lens for a DSLR/DSLM camera, worth hundreds of dollars, if you ask for a macro lens.