Help with MicroSD card

Im using M3 DS Simply to run my Nintendo DS Roms.Using a 1GB sandisk MicroSD card to hold the games.When I try to delete games and add more through my PC
even though the games I delete from the card no longer show
the space they occupied on the Microsd card is still taken up.even if I delete every thing from the card it still shows the same amount if memory being used.
The only way so far I can regain the space is to format the card again, which sucks... >:(anyone have any helpful info on this problem?TIA

formatting the card wont do any damage, and it sounds like it needs it.

Replying to #2

yeah but every time?

it shouldnt need it every time, but if it does it still wont damage it