wizard83,
I suspect you have a hacked player with only128MB memory chip. Formating the player has removed the hack and your chip is now reading it's correct size.
To verify your memory chips true size you will need to open the player and check the serial number of the chip against
THIS list of Samsung and Hynix chips.
Quite often hacked chips will appear as 2 drives.
If you look through the forums you will find many posts from other people who have had hacked players.