Why am I getting an error telling me that I am attempting to perform an arithmetic on an Object?

I am trying to round values up in a function. However, before I even call that function, I get an error telling me that I am trying to perform an arithmetic on an Object. I believe the script thinks that the function's parameter is a 'userdata value'. Here is the code:

Server Script:

local movePartEvent = game.ReplicatedStorage.MovePartEvent

local function round(X)
    return math.ceil(X + .50)
end

movePartEvent.OnServerEvent:Connect(function(...)   
    local tuppleArgs = {...}
    local player  = tuppleArgs[1]
    local value1  = tuppleArgs[2]
    local value2  = tuppleArgs[3]
    local value3  = tuppleArgs[4]

    game.Workspace.MovingPart.CFrame = CFrame.new(round(value1), 1, round(value3))
end)

Client Script:

local player = game:GetService("Players").LocalPlayer
local mouse = player:GetMouse()

script.Parent.MouseButton1Click:Connect(function()
    print("Clicked")

    while true do 
        game.ReplicatedStorage.MovePartEvent:FireServer(player, (mouse.Hit.X), (mouse.Hit.Y), (mouse.Hit.Z))
        wait(0.50)
    end
end)

Thanks in advance!

Edit: I added the client script, although I don't think it has anything to do with my error. That is because I receive the error in my Server Script, on a function that I haven't even called yet.