Anyone knows how to pry open the seat belt buckle?

Someone broke the passenger side window and stole the gps from my 2004 prius. I got the window replaced but just found out that a small piece of glass fell in the opening of the passenger seat belt buckle. It was visible and I almost got it out, but I failed in the last second and it fell under now I can't see it anymore. Now when I push the button on the buckle, it only goes half way down. It still kinda work but sometimes it is difficult to lock the seatbelt in. Is there a way I can took the buckle apart and fix it?