I doubt many people even still play this game, let alone had it at some point, but having had a little trouble on this trophy thought I'd explain quickly why. This is mind you doing this the legitimate way, for anyone wanting to get this quickly, I'm sure you can just edit you PS3 clock, and get it that way.
But for those playing normally, what you have to do that isn't mentioned in the description is play for 3 consecutive weekends ALL IN THE SAME MONTH. I played across the end of December, beginning of January, only for nothing to happen. Turns out this is why, so just make sure you ideally start in the first half of the month, to avoid playing more than you might have wanted too.