Unable to cast to Dictionary tween

[Szadouuuu (Szadou)]

I was simply trying to make a model rotate every 5 secs, but when I started the game, there was an issue in line 18 (the one creating the tween) while the output was “Unable to cast to Dictionary”. From what I learned, this message should appear when trying to put more than 3 arguments there

local TS = game:GetService("TweenService")
local part = script.Parent.Cylinder

local RotationRatio = 0.125

local RotValue = RotationRatio * 360
local EndPos = part.CFrame * CFrame.Angles(math.rad(RotValue), 0, 0)

local tweenInfo = TweenInfo.new(
	0.85,
	Enum.EasingStyle.Sine,
	Enum.EasingDirection.In,
	0,
	false,
	0
)

local tween = TS:Create(part, tweenInfo, EndPos) --here

while true do
	tween:Play()
	wait(5)
end

[My47thChromosome]

The third argument needs to be a dictionary/table:
local tween = TS:Create(part, tweenInfo, {EndPos})

[DasKairo (Cairo)]

TweenService:Create() requires the third argument to be a Dictionary in order to process it.
This is to allow you to change more than one property of your object, which is formatted as:
{property = value}

For Example, if I wanted to change a Parts color, and its rotation, I would tell TweenService using a Dictionary, as such:

{Color = Color3.new(1,0,0); Orientation = Vector3.zero}
-- I need to define what to change in order for it to do it correctly
-- Color is defined for Coloring
-- Orientation is Defined in order to Rotate it

[Miserable_Haven]

i never knew that you could tween multiple properties of an instance by adding semicolon

[devmaxcat (Max)]

The third argument of a tween is supposed to be a dictionary value, which would be written like this in your case
TS:Create(part, tweenInfo, {CFrame = EndPos})