i got the Samsung 128 evo class 10 card i put it in my mac computer it say it does not recognize this card. before i did that for past week i watch and download clips from the phone app.
Format the card on your Mac using FAT32. Then the Mac and your M6+ will both be able to read it. If you format it in the camera, your Mac won't be able to mount the card. Windows will, so if you have a Windows computer, you can view them there.