So we can better assist you, please provide a brief description of your current setup using this link as a guide.
Make sure to describe your network configuration/topology, including any networking hardware currently in use, so we can have a clear understanding of how your devices are communicating.
We have some great documentation here about setting your NAS up in Roon. You’ll want to make sure that the music folder is properly shared and then use the correct path.
Also make sure to use the correct Username and Password for the share.