In Soul Silver Brock offers a trade of a Bonsly for a Rhyhorn that knows Thunder Fang but after speaking to him I went to get a Bonsly and he's never reappeared in Diglett's Cave again. I was told that I had to beat him in a rematch again but I did so yesterday and he's not reappeared between noon and 3PM like Bulbapedia said. I've spoken to him before but after he offered to trade he's disappeared. Any one know what's happened and if Brock will appear again or if there's a different day/time that I find him for the trade which no one's told me? Thanks in advance.