Lens profiles aren't for camera models, they are for lenses. What lens are you using? The camera model the lens was created with shouldn't matter as long as it's full-frame, or for crop-frame cameras as long as it's from a full-frame or crop-frame camera.
If you are working with DNGs from a previous, recent version of LR, then the metadata could be messed up and that's why the profile cannot be found. Or if you are viewing a JPG, then profiles for JPGs aren't usually made and are different than profiles for raw files.
Would you mind sharing one of your raw files, upload to dropbox, post a public-share link, here?