What is "Unable to cast string to int64"?

Hello!

So I know that Roblox updated how GamePassService works, and I've been using one of their teleport models for ages, that worked just fine until the latest update. I thought I'd fixed my code here with the new terms, but I'm getting this error for Line 37 "Unable to cast string to int64" What is this? I've never seen this, and am unsure how to correct it.

Script below:

--------------------
--| WaitForChild |--
--------------------

-- Waits for parent.child to exist, then returns it
local function WaitForChild(parent, childName)
    assert(parent, "ERROR: WaitForChild: parent is nil")
    while not parent:FindFirstChild(childName) do parent.ChildAdded:wait() end
    return parent[childName]
end

-----------------
--| Variables |--
-----------------

local GamePassService = game:GetService('GamePassService')
local PlayersService = game:GetService('Players')
local DebrisService = game:GetService('Debris')

local Teleporter = script.Parent

local GamePassIdObject = "rbxassetid://879190380"
local ExitLocationObject = WaitForChild(script, 'ExitLocation')

local JustTouched = {}

-----------------
--| Functions |--
-----------------

-- When a player with the game pass touches the door, teleport them to the other side
local function OnTouched(otherPart)
    if otherPart and otherPart.Parent and otherPart.Parent:FindFirstChild('Humanoid') then
        local player = PlayersService:GetPlayerFromCharacter(otherPart.Parent)
        if player and not JustTouched[player] then
            JustTouched[player] = time()
            if game:GetService("MarketplaceService"):UserOwnsGamePassAsync(player, GamePassIdObject) then
                local character = player.Character
                if not character:FindFirstChild('JustTeleported') then
                    local justTeleported = Instance.new('StringValue')
                    justTeleported.Name = 'JustTeleported'
                    DebrisService:AddItem(justTeleported, 0.3)
                    justTeleported.Parent = character
                    character:MoveTo(ExitLocationObject.Value)
                end
            end
        end
    end
end

-- Removes old entries in JustTouched
local function RemoveOldTouches()
    for player, touchTime in pairs(JustTouched) do
        if time() > touchTime + 0.3 then
            JustTouched[player] = nil
        end
    end
end

--------------------
--| Script Logic |--
--------------------

Teleporter.Touched:connect(OnTouched)

while true do
    RemoveOldTouches()
    wait(1/30)
end