Animation doesn't play even though isPlaying is true

[1Galaxity1 (Galaxity)]

1. What do you want to achieve?: Im trying to make a running system which winds up the run and when you reach max speed, plays an animation.

2. What is the issue?: The Animation doesn’t play, but isPlaying returns true

3. What solutions have you tried so far?: The animation is made by me, i tried setting its priority to “Action”, I’ve tried playing it in a local script but nothing worked

local ReplicatedStorage = game:GetService("ReplicatedStorage")
local Players = game:GetService("Players")

local FunctionsFolder = ReplicatedStorage:WaitForChild("Functions")
local StartRunFunction = FunctionsFolder:WaitForChild("StartRun")
local StopRunFunction = FunctionsFolder:WaitForChild("StopRun")

local movement = {}

local runAnimID = "rbxassetid://17705765971"
local isRunning = false

local runLoop = coroutine.create(function(player)
	local humanoid = player.character:FindFirstChildOfClass("Humanoid")
	assert(humanoid, "No Humanoid found!")
	local animator = humanoid:FindFirstChildOfClass("Animator")
	assert(animator, "No Animator found!")

	local runAnim = Instance.new("Animation")
	runAnim.AnimationId = runAnimID
	runAnim.Parent = player.character
	local track = animator:LoadAnimation(runAnim)
	while true do
		if isRunning then
			humanoid.WalkSpeed = humanoid.WalkSpeed + 7
			if humanoid.WalkSpeed >= 64 then
				humanoid.WalkSpeed = 64
				if track and not track.IsPlaying then
					track:Play()
					print(track.IsPlaying)
				end
			end
			print(humanoid.WalkSpeed)
			wait(0.3)
		else
			humanoid.WalkSpeed = humanoid.WalkSpeed - 20
			if humanoid.WalkSpeed <= 16 then
				humanoid.WalkSpeed = 16
				if track and track.IsPlaying then
					track:Stop()
				end
				coroutine.yield()
			else
				wait(0.3)
			end
		end
	end
end)

function movement.StartRun(player)
	isRunning = true
	coroutine.resume(runLoop, player)
end
StartRunFunction.OnServerInvoke = movement.StartRun

function movement.StopRun(player)
	isRunning = false
end
StopRunFunction.OnServerInvoke = movement.StopRun

return movement

[1Galaxity1 (Galaxity)]

I’ve noticed that using a animation made by roblox works but mine doesn’t.

[1Galaxity1 (Galaxity)]

oh nvm my avatar was r15 and the animation is r6