Crossmann

So I'm having some trouble with Charlotte and when I say trouble I mean I can't get past her first two pokemon. My current team as of writing this is Mamoswine- level 57 with Thick Fat, NeverMeltIce, and (I'm not sure if nature matters) Jolly. AncientPower, Ice Fang, Earthquake, Blizzard Mamoswine- level 56 with Thick Fat, Icicle Plate, and Impish. AncientPower, Ice Fang, Earthquake, Blizzard Roserade- level 63 with Technician, Rose Incense, and Hasty Mega Drain, Grassy Terrain, Nature Power, Stun Spore Simipour- level 60 with Gluttony, Mystic Water, and Jolly Brine, Surf, Dive, Crunc