OK then, so don't dump it. If you're happy to risk it, use it in another device and then use the working Samsung card in the 807.
It seems you're looking for a technical answer to fix the card, so you can go back to using it in the 807 when, frankly, there isn't one. I had a Pro Sandisk 64gb MicroSD card that refused to work in one of my DJI quads, which worked in it without a single issue for more than 18 months, but then, suddenly during a flight, it just stopped. It'd format fine but just wouldn't record and yet it worked in another DJI quad perfectly! Why's that then??! Although it was annoying, I honestly didn't really care, so I chucked the card and replaced it, as I did not want to risk it failing once again during a flight. My advice is worry about it - life's too short; forget it and move on mate....
It seems you're looking for a technical answer to fix the card, so you can go back to using it in the 807 when, frankly, there isn't one. I had a Pro Sandisk 64gb MicroSD card that refused to work in one of my DJI quads, which worked in it without a single issue for more than 18 months, but then, suddenly during a flight, it just stopped. It'd format fine but just wouldn't record and yet it worked in another DJI quad perfectly! Why's that then??! Although it was annoying, I honestly didn't really care, so I chucked the card and replaced it, as I did not want to risk it failing once again during a flight. My advice is worry about it - life's too short; forget it and move on mate....