Why won't my phone read my sd card?

[AC Question]

I have a prepaid smartphone. Its an LG optimus exceed 2 and it's not reading my sd card. I used the card in my last phone with no problems. It shows that a card is being inserted and removed, but it won't let me mount it. Its done this from day one. Anyone know what I can do??

 

[hmb0493]

Change the card if possible. How much is it's capacity ?