[rotab]

Something like this?

PHP Code:

public OnClientPostAdminCheck(client)
{
    decl String:name[64];
    GetClientName(client, name, sizeof(name));
    
    if (StrEqual(name, "SteamPlayer", false))
    {
        new String:reason[32] = "nick";
        new String:kickMessage[32] = "Fix your nick";
        BanClient(client, 1, BANFLAG_AUTHID, reason, kickMessage);
    }
}