Dragon Slayer GB DMG saving issue

For some reason I'm not able to save the game into Dragon Slayer game on my GB DMG with Ez Flash Junior.

Some other games seems to be working since the files are created into the Saver folder.

Do I have to do something special? I have read something about patching the game, but the Ez Client does not recognize the .gb file.

I also have checked the battery voltage (2.9V)

Thanks to anyone who can help!