Bad argument #3 to 'Position' (expected Vector3, got object) how do I fix it?

I want to change the position of the part based on the CFrame of the mouse, but I get this error: Bad argument #3 to 'Position' (expected Vector3, got object) I am using a RemoteEvent to transfer the CFrame value from the client to the server.

Here is the LocalScript:

local replicatedstorage = game:GetService("ReplicatedStorage")
local Player = game.Players.LocalPlayer -- Also, I noticed you weren't using 'local' to define your variables. Use that, as it sets the variable apart from a global variable.
local Mouse = Player:GetMouse()
local MouseCFrame = Mouse.Hit
local MousePosition = MouseCFrame.p

local event = replicatedstorage:WaitForChild("TestEvent")

function printpos()
	MouseCFrame = Mouse.Hit
	MousePosition = MouseCFrame.p
	event:FireServer(MousePosition)
	print (MousePosition)
end

Mouse.Button1Down:Connect(printpos)

Here is the Script for the server:

local replicatedstorage = game.ReplicatedStorage
local event = Instance.new("RemoteEvent")
event.Name = "TestEvent"
event.Parent = replicatedstorage

local part = game.Workspace.test

function movePart(coords)
	part.Position = coords
	print(coords)
end

event.OnServerEvent:Connect(movePart)

it doesn't work because in the script (not the localscript) the coords variable is actually the player who fired the remote event so do this

local replicatedstorage = game.ReplicatedStorage
local event = Instance.new("RemoteEvent")
event.Name = "TestEvent"
event.Parent = replicatedstorage

local part = game.Workspace.test

function movePart(plr,coords)
	print(coords)
    part.Position = coords
    
end

event.OnServerEvent:Connect(movePart)