Why is my ball not getting kicked up in the air?

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if magnitude <= 9 or ball.Velocity ~= Vector3.new(0, 0, 0) and magnitude <= 20 and ball.LastTouch.Value == player.Name then
            print(magnitude, "shot")

            ball.Velocity = Vector3.new(0, 0, 0)

            local mover = Instance.new("BodyVelocity")

            local amount = argument2

            print(argument2)

            local pos = (character.HumanoidRootPart.CFrame.lookVector.Unit + Vector3.new(0, 0.95, 0)) * 2

            pos = pos * argument2

            print(pos)

            ball.Velocity = pos

            wait(4)

            player.CanShoot.Value = true

            for i, v in pairs(character:GetChildren()) do
                if v:IsA("BasePart") or v:IsA("MeshPart") or v:IsA("Part") then
                    physicsService:SetPartCollisionGroup(v, "Default")
                end
            end

https://gyazo.com/7c01280be2f3a615ca0bc4c2f85dff53

When i kick the ball, it isball is supposed to get flung in the air, but it sometimes does and sometimes it doesnt, i dont know why. I didnt post the whole script and only the necessary part since i thought it wasnt important. Help pls

Thx