Find Color identifying Paper as a PMS?

InDesign has always identified that which usually appears white in a document as "paper". This is because in most cases what appears to be white in a printed piece is actually the white of the paper that the job is printed on. It is not usually attained by using white ink. If you are printing a job on a colored paper then you can redefine the "paper" as the color of the paper to be used and that color will now no longer separate out as a color to be printed. In the case of the issue that you are reporting double click on the paper entry in the swatch panel and see if the paper option has been redfined as the color that you are looking for. Another thing to consider is that most PANTONE books are no longer actually part of the Creative Cloud programs anymore. You need a separate subscription with PANTONE to actually have most of their libraries available in a document. What is happening could be a result of not having the PANTONE library actually available.