Rhino export settings _help please

I made a simple dog tag in Rhino
But when exporting it adds strange polygons, I couldn’t find the solution
does anyone know

I am using rhino 7 file is attached

ResimLink - Resim Yükle

rhino file WeTransfer - Send Large Files & Share Photos Online - Up to 2GB Free

Based on the image, it just looks like your mesh creation settings are way too coarse.

I would recommend a two step process…
Once you have a closed, solid, poslysurface model in Rhino, run the Mesh command and fiddle with the settings until you like the density and fit of the mesh for you needs.

Then Export just the resulting mesh to STL.

See if this works better:

kop mesh.stl (70.4 KB)

Thanks a lot, I got a decent output using these settings