Shin Megami Tensei Devil Survivor (saving)

I currently play SMT on an R4 card. The problem I have is, I save the game then turn off the DS. When I turn the DS back on, the game doesn't recognize that I saved the game before. I basically have to start the game over again every single time I want to play. Any idea what the issue might be?

have you upgrade your R4?

This thread should be in Technical Help section.It should be covered here. Common Issues or .Super Easy Way to get games working on an R4

What is your firmware?