Mining GUI health bar not working properly?

I am creating this mining ore for no reason what so ever and I set up a health bar and I want it to stay while the player is mining but I want it to go away while they're not. The problem is, it glitches and stuff like that. Whenever you spam click the ore it will pop up then go back down really quickly.

Local Script:

local cursors = {
    equip = "rbxassetid://117431027",
    unequip = ""
}

local tool = script.Parent
local player = game.Players.LocalPlayer
repeat wait() print("Waiting for player...") until player
local character = player.Character
repeat wait() print("Waiting for character...") until character
local box = script.Parent:WaitForChild("Selector")
local mainUI = player.PlayerGui:FindFirstChild("MainUI")
local damageEvent = game:GetService("ReplicatedStorage").Remotes.DamageOre
local deleteEvent = game:GetService("ReplicatedStorage").Remotes.DeleteOre
local config = require(script.Parent:WaitForChild"Config")
local damage = false

tool.Equipped:Connect(function(mouse)
    mouse.Icon = cursors.equip

    mouse.Move:Connect(function()
        if mouse.Target then
            if mouse.Target.Name == "Ore" then
                local humanoid = character:FindFirstChild("HumanoidRootPart")

                if(mouse.Target.Position - humanoid.Position).magnitude < 30 then
                    if mouse.Target:FindFirstChild("Selector") then return end
                    box.Visible = true
                    box.Adornee = mouse.Target
                else
                    box.Visible = false
                    box.Adornee = nil
                end
            else
                box.Visible = false
                box.Adornee = nil
            end
        end
    end)

    mouse.Button1Down:Connect(function()
        if mouse.Target then
            if mouse.Target.Name == "Ore" then
                local target = mouse.Target
                local oreName = target:WaitForChild("Name")
                local oreHealth = target:WaitForChild("Health")
                local oreMaxHealth = target:WaitForChild("MaxHealth")
                local oreHealthUI = mainUI.OreHealth
                local oreCurrentHealth = oreHealth.Value/oreMaxHealth.Value

                oreHealthUI.Visible = true

                oreHealthUI.HealthBar.Percent.Text = oreHealth.Value.."/"..oreMaxHealth.Value.."%"
                oreHealthUI.HealthBar.Fill:TweenSize(UDim2.new(oreCurrentHealth, 0,1, 0), Enum.EasingDirection.InOut, Enum.EasingStyle.Linear, 0.2)

                if oreHealth.Value == 0 then
                    deleteEvent:FireServer(target)
                end

                damageEvent:FireServer(target, config.damage)
                damage = true

                wait(3)

                damage = false

                if damage == false then
                    oreHealthUI.Visible = false
                end
            end
        end
    end)
end)