(Answered) Jet Pack works to fly but can't move on X and Z?

I made a jet pack which works to fly when I hold down E, but for some reason when I hold down E it works to fly up but I can't move around using the WASD or Arrow keys? It works to move around when I'm in the air only if I'm not holding down E.

local UIS = game:GetService("UserInputService")
local HoldingE = false
local YVelocity = 0

UIS.InputBegan:Connect(function(inputObject) 
    if(inputObject.KeyCode == Enum.KeyCode.E)then
        HoldingE = true
        while HoldingE do
    YVelocity = YVelocity + 10
    script.Parent.JetPack.Handle.BodyVelocity.MaxForce = Vector3.new(4000, 4000, 4000)
    script.Parent.JetPack.Handle.BodyVelocity.Velocity = Vector3.new(0, YVelocity, 0)
            wait(0.1)
        end

    end
end)
UIS.InputEnded:Connect(function(inputObject)
    if(inputObject.KeyCode == Enum.KeyCode.E)then
        HoldingE = false
        YVelocity = 0
        script.Parent.JetPack.Handle.BodyVelocity.MaxForce = Vector3.new(0, 0, 0)
    end
end)

I've tried removing this part of the script:

    YVelocity = YVelocity + 10
    script.Parent.JetPack.Handle.BodyVelocity.MaxForce = Vector3.new(4000, 4000, 4000)
    script.Parent.JetPack.Handle.BodyVelocity.Velocity = Vector3.new(0, YVelocity, 0)
            wait(0.1)
        end

And when I removed that part I was able to move using the WASD and Arrow keys, so I would assume that the problem is something to do with the body velocity? (I'm New With Body Velocity)