Me and my friends are playing the pixelmon reforged mod on an aternos server. However don't matter what we do, we can't find any biome beside savannah, darkwood forest, swamp, desert and plains. (this also happens on singleplayer worlds).

I did find other biomes after a short search, the cause most definitely isn´t on our side, more like that Minecraft generation screwed up at some point, so I don´t consider this as a bug we could fix