Avalon Code (game freezes after second save)

I've been having problems with the Avalon Code game for Nds.
I use the r4. The first time I save, it works fine. But the second time I try to save the file, it freezes!
And time to time it randomly freezes! It's so frustrating...
Can anybody help me?

https://www.romulation.org/forum/index.php?topic=1462.0