Tapeworm,
There’s no need to be abusive. You are talking to a customer of Sandisk (even if they have made a small mistake with the name). If you have any evidence that this is a troll, do share it, otherwise be more polite.
There is obviously a problem with thes (sorry, these) cards. I have had a 32gb card do the same thing in a Galaxy S4 and a 128gb card in a Galaxy Note 4. Both lost all the data on them, so now do we trust them or back them up regularly or what? Samsung gives us the facility to move apps to the SD card, so suddenly losing apps as well as data can be very inconvenient. We do need to rely on the SD card from hour to hour even if we back up every day.
Both mine were replaced and upgraded (the 32gb to a 64gb and the 128gb to a higher class) by Sandisk, but not without a lot of messing and sending the faulty cards back. It is, however, as you suggest, always worth taking the case up with Sandisk who do not quibble providing the card is genuine.
