Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Great for the first few months

I bought this card in January, and used it off an on for several months. It worked great, my data was always intact. Now, I've been using the card with my GameCube on an almost daily basis, and nearly everytime I start the GameCube up, whatever game I have in there informs me that the memory card is corrupt and must be formatted.I have not found a solution, and the card has rendered itself useless. I regret saving a few dollars on a subpar memory card. I have not had any issues of this nature with genuine Nintendo cards.