Unable to cast Dictionary to TweenInfo?

I was trying to make a repeating and tweening camera using while true do and tweeninfo. The current camera CFrame starts on the first camera and would switch into the second camera every 7 seconds with a tween and also on repeat.

local camera = workspace.CurrentCamera
camera.CameraType = Enum.CameraType.Scriptable

local tweenService = game:GetService("TweenService")

function tween(part1, part2)
    local tweenInfo = TweenInfo.new(5,Enum.EasingStyle.Quad,Enum.EasingDirection.Out)
    local tween1 = tweenService:Create(camera, TweenInfo, {CFrame = part2.CFrame})
    local tween2 = tweenService:Create(camera, TweenInfo, {CFrame = part1.CFrame})
    while true do
        camera.CFrame = part1.CFrame

        tween1:Play()

        wait(7)

        tween2:Play()

        wait(7)
    end
end

tween(game.Workspace.Cam1, game.Workspace.Cam2)