Twitch name on map

[mrspakrninja]

Before I bought the game on my Steam account, my son logged on to his on my computer, downloaded it and played it. I have since bought it on my Steam. But every time I try to generate a map, it shows his name as the guy. I've uninstalled the game on my computer and deleted all the files, and I am, of course, logged into my steam, but it still shows up with his name. I'm trying to stream on Twitch, and I'd rather not have his Twitch name on my channel. Any suggestions?

[Bilka]

Options -> Other -> Change the name there