Gui position to mouse position not working as expected?

So, I have this script to, when the player hovers over the part, for a gui to show then always move to the player's mouse position until the player gets to far or stops hovering over the part. LocalScript in Frame

wait(1)

local player = game.Players.LocalPlayer
local mouse = player:GetMouse()
local target = mouse.Target
local gui = script.Parent

gui.Visible = false

mouse.Move:connect(function()
    if target.Name == "lookpartforchest" and (game.Workspace.lookpartforchest.Position - player.Character.Torso.Position).magnitude <= 12 then
        gui.Visible = true      
        repeat      
        gui.Position.X = mouse.X
        gui.Position.Y = mouse.Y
        wait(0.01)
        until
        target.Name ~= "lookpartforchest" or  (game.Workspace.lookpartforchest.Position - player.Character.Torso.Position).magnitude >= 12
        gui.Visible = false
    elseif not target then
        gui.Visible = false
    end
end)

Sorry if the error is so obvious, I was tired while making this and haven't used mouse.X and mouse.Y before.