Violation Of Creative Commons License

I received an email the other day with the question if I was aware that someone was selling 3D prints of one of my designs.

I make my designs available with the following license: Creative Commons - Attribution - Non Commercial. So what does this mean?

​Creative Commons - You are free to share and/or remix/change my designs.

Attribution - ​​​You must give appropriate credit, provide a link to the license, and indicate if changes were made.

Non Commercial - You may not use the material for commercial purposes.

Unfortunately they are not responding to my email and message to remove it from their website. My license clearly states non commercial and on the website that sells these there is not a single reference to the original source or attribution.