I really like your avatar, I can't say the same to your post though, first of all: What are you talking about? Setprefix is not a vanialla pmmp command... 2nd This is probably the wrongest forum section to out that post in, I recommend you to take a look at this: https://forums.pmmp.io/threads/where-should-my-thread-go.14/ Now my try to give a helpful answer: I assume you are talking about PureChat, if so there's what you're looking for: https://github.com/PurePlugins/PureChat/blob/master/plugin.yml#L37
Oh... i thought that that command was part of pocketmine! I didnt know that it was part of PureChat... Silly Me