Bodygyros and Camera CFrame is not working???

This a flying script that's supposed to rotate the body when the player moves their camera. It works but when the player has a 2-handed weapon equipped and they press V to start flying, they can't move their body up/down when moving their camera. Can anyone explain why this is happening?

Here is a part of the script

game.Players.LocalPlayer.Character:findFirstChild("Torso") 
game.Players.LocalPlayer.Character:findFirstChild("Humanoid") 
local mouse = game.Players.LocalPlayer:GetMouse() 
repeat wait() until mouse
local plr = game.Players.LocalPlayer 
local root = plr.Character:WaitForChild("HumanoidRootPart") 
local flying = false 
local ctrl = {f = 0, b = 0, l = 0, r = 0} 
local lastctrl = {f = 0, b = 0, l = 0, r = 0}  
local speed = 60

function Fly()
    local bg = Instance.new("BodyGyro", root) 
    bg.P = 9e4 
    bg.maxTorque = Vector3.new(9e3, 9e3, 9e3) 
    bg.cframe = root.CFrame 
    local bv = Instance.new("BodyVelocity", root) 
    bv.velocity = Vector3.new(0,0,0) 
    bv.maxForce = Vector3.new(9e9, 9e9, 9e9) 
        repeat wait() 
        plr.Character.Humanoid.PlatformStand = true 
            if (ctrl.l + ctrl.r) ~= 0 or (ctrl.f + ctrl.b) ~= 0 then 
                bv.velocity = ((game.Workspace.CurrentCamera.CoordinateFrame.lookVector * (ctrl.f+ctrl.b)) + ((game.Workspace.CurrentCamera.CoordinateFrame * CFrame.new(ctrl.l+ctrl.r,(ctrl.f+ctrl.b)*0,0).p) - game.Workspace.CurrentCamera.CoordinateFrame.p))*60
                lastctrl = {f = ctrl.f, b = ctrl.b, l = ctrl.l, r = ctrl.r} 
            elseif (ctrl.l + ctrl.r) == 0 and (ctrl.f + ctrl.b) == 0 and speed ~= 0 then 
                bv.velocity = ((game.Workspace.CurrentCamera.CoordinateFrame.lookVector * (lastctrl.f+lastctrl.b)) + ((game.Workspace.CurrentCamera.CoordinateFrame * CFrame.new(lastctrl.l+lastctrl.r,(lastctrl.f+lastctrl.b)*0,0).p) - game.Workspace.CurrentCamera.CoordinateFrame.p))*0 
            else 
                bv.velocity = Vector3.new(0,0,0) 
            end 
        bg.cframe = game.Workspace.CurrentCamera.CoordinateFrame 
        until not flying 
            ctrl = {f = 0, b = 0, l = 0, r = 0} 
            lastctrl = {f = 0, b = 0, l = 0, r = 0} 
            speed = 0 
            bg:Destroy() 
            bv:Destroy() 
            plr.Character.Humanoid.PlatformStand = false 
        end