Have I broken my SD2Vita?

Decided I wanted to try SD2Vita and have a bit more storage space to work with. Ordered the adapter and a legit Sandisk 128gb stick and started following the guides. All was going well until I started copying files from ux0 to uma0 where I got error 0x80010005.

After some Googling, I realised it could be that files were too big, read only, etc. so decided to give it another go, folder by folder. Upon opening VitaShell again, uma0: wasn't mounted anymore. Trying to mount it again asks me to insert the card, and trying to format the card again in VitaDeploy gives me a Format failed C1-2755-9 error.

To the Vita, the card just doesn't exist anymore. I've heard that the adapters can go bad, but could it have broken so quickly? Any information or ideas would be great. Thanks