Why does my Micro SD card say that I don't have enough space on it when I do!?

I use a 32gb SanDisck Micro SD card to store my music in my Samsung Galaxy tablet and I wanted to add more songs to the card, Since I wasn’t really sure what songs I didn’t have on it, I decided to swipe the card clean (all it had was my music) and went to transfer my iTunes Media folder into it. However, it says there isn’t enough space, which is not true because my music library only uses 12.91 GB. I tried transferring my music a few at a time instead of all at once but I can barely transfer 1/4 of my music library before it says that there isn’t enough space. 

I’ve heard that reformatting the card or something of the sorts might help but I haven’t the slightest clue on how to do that. 

If it makes any differences, I’m using a MacBook Pro. 

I would really appreciate some help in this matter. Thanks in advance! :slight_smile:

When deleting files from a memory card through your Mac, you have to empty your Trash before pulling the card. Otherwise, all it does is delete the reference (fila names) to them.