HELP ME!!

I need help here. when i defeated the dark Valefor, I met 2-3 monsters, but after that, I just cant meet any monsters. I dont now what I now should do. I only can meet dark Aons. My brother has a game, were he not have deafeted Dark Valefor, and can meet monsters. Why can i not? Please help me.

. . .Do you have any no encounters armor (or the weapon from geosgaeno) equipped?

Generally that's the problem, it seems.