Samsung SD card not readable by this device

I have a 64 GB Samsung SD card that is completely full and I'm trying to transfer files to my MacBook Pro or MAC. I have transferred files from this same card to these same computers before. Both give me the same error, unreadable by the computer. I've run the disk utility first aid. It says operation successful. Cannot open the card, only options are first aid, erase, restore.

How do I get this thing open without losing my files?