Hello, Our kid got me this reader and card for fathers day especially for my RPI3B+ i have been using it without a problem since and until this morning. After transferring all the info to my win10 machine, I decided to re-format my 64g from 2x32 partitions back to 1x64g partition and all this on another linux mint laptop. All went as usual but just after the re-format i received an error that flashed open and closed too fast to read. I can no longer mount the reader on my linux-laptop or the raspberry pi. If i put the reader on an old win7 laptop the drive is detected and mounted automatically. So the reader does work.
If i remove the card and use it in the reader that came with the RPI it mounts itself on both linux machines and i can see that the full 64g partitionis there.
Conclusion…something with the sandisk reader is preventing any linux machine from mounting it but i have no idea what or where else to look after 4 hours of hardcore googling on both windows info and linux.
If anyone here has had or heard of a similar issue and a solution i could really use some help here. It would be a shame if i can no longer use the reader with the PI it’s the perfect size and also our kid doesn’t have money to throw away. It’s not even a year old 
EDIT: 20 minutes after.
The card was formatted again back to 2x32 fat32 using another reader.
