Unformat-able SD Card

[komputes]

I had an SD card with Ubuntu running on it and I took it out during the 
shutdown process, while the computer was still on. This card booted two 
or three times but then I noticed that there were errors and  changes 
back to  default, I could not explain it. When I got it home, the bios 
could not even recognize the disk,  When I try reformatting it in 
gparted it gives me a negative value for the size of the drive, does 
anyone have a clue what could have happened to this card and how I could 
I possibly fix it? None of my SD devices can format this card - it only 
gives me a "card error".