How can I only activate a chat-activated function when they are close enough?

I have an easter egg with a text label that will only show up when the player is close enough to the Part. I've tried getting the distance, but either I'm using the wrong thing entirely or there's a minor error in there. But mostly the thing I can't seem to figure out is how to get the position of the player, as it says that HumanoidRootPart is not a valid member of player.

game.Players.PlayerAdded:Connect(function(player)
    player.Chatted:Connect(function(msg)
        if msg == "message" and player.HumanoidRootPart.Position - workspace.TreeSecret.Trunk <= 10 then
            script.Parent.SurfaceGui.TextLabel.Visible = true
            wait(0.5)
            script.Parent.SurfaceGui.TextLabel.Visible = false
        end
    end)
end)

Thanks