If it has data on it, you shouldn't format it, because then you lose all that data. So it's quite good you can't format it.
Only try to format it after you copied all data on it that you want to keep to (1) a safe place, and (2) a equally safe backup. When you have those 2 copies, you can try to fix the card or throw it away if that doesn't work.
If copying doesn't work on your PC, try another card reader or another PC.
If for some reason you can't read all data from the card, and you don't have a backup of that data on some other medium, I'm afraid you lost those. That's a well-known risk of not having a backup.
My SD card wont format and apparently it has no free space or used space and im just so stressed as it was an expensive sd and it has data on it. Help

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