It is normal that apps and connected devices don't see the SD Card if set as "Internal Memory", anyway you can access it via the File Manager stock app.
Of course to make that visible in any case you have to set it as a portable memory. But like so you won't be able to store apps in the sd card, nor you could choose the sd card as the default camera/other app storage.
i'm using it as Internal Memory. Like so, if you connect the phone to a PC, and tap the Transfer File option on your phone, you will be able to access the sd card (and that only), by the file explorer.