If you're still at location 198 then clearly thats where you did wrong lol. As we said since the first gambit, use ur peronamins that u have stored in time to reach location 100 and 200 in the first or second day it's available.
Once u are there the chance time will appear more often and also the prize of getting the right choice of an EX stage, can be 100 or 300 stamps.