[IstuntmanI]

You must to have

Код:

return SendClientMessage(playerid, RED, "That is an unknown command! Type /cmds for a list of available commands.");

so will be:

Код:

public OnPlayerCommandText(playerid, cmdtext[])
{
    //stuff
    //another stuff
    return SendClientMessage(playerid, RED, "That is an unknown command! Type /cmds for a list of available commands.");
}