SD card question

invalid@example.com (chimpboy74), chimpboy74
Wed, 06 Nov 2019 18:50:43 +0000
Nokia 7 Plus

I am slowly running out of space on my 7 plus (in spite of backing up photos etc). I have an SD card inserted which seems to be recognised but I am trying to move some of my apps to the SD card to free up internal storage but when I follow the instructions for this no app appears to be able to move. Am I just unlucky as I know some apps can't be on external storage but I would have thought at least one or two of my apps could be moved there. Have I missed something obvious to be able to...