Well, the only way to have it allow you to move apps is that you have to have set the SD card as internal storage, which must be done prior to putting anything on the card. If you haven't set it up to be internal yet, I will include the instructions below. If you have already set it to be internal then the problem may be in the way you are reading it. Once the card is changed over, the apps can show as being on both the card and the phone. It is annoying sometimes. The only way to avoid that is to uninstall the app completely and download it directly to the card.
How to turn external SD card into internal storage on "Marshmallow".
NOTE: Please be sure you start with a blank SD card. It needs to be blank because when the card is...