Why does this crash my Game?

[boreal stump]

** You are now Level 1! **

[tacit nexus]

local reloading = false
local UIS = game:GetService("UserInputService")
local Ammo = 32

--Crosshair Appearing
script.Parent.Equipped:Connect(function()
game.ReplicatedStorage.GunValue.Value = true
end)
script.Parent.Unequipped:Connect(function()
game.ReplicatedStorage.GunValue.Value = false
end)

M = game.Players.LocalPlayer:GetMouse()
--Shooting/Ammo
script.Parent.Activated:Connect(function()
while M.Button1Down and wait(0.1) do
wait(0.1)
if Ammo > 0 and reloading == false then
wait(0.1)
game.Workspace.pistol_fire:Play()
Ammo = Ammo - 1
game.ReplicatedStorage.AmmoInMag.Value = Ammo
local MOUSEPOS = game.Players.LocalPlayer:GetMouse()
if reloading == false and MOUSEPOS.Target.Parent:FindFirstChild("Humanoid") then
print("PLAYER")
MOUSEPOS.Target.Parent.Humanoid.Health = MOUSEPOS.Target.Humanoid.Health - 10
end
end
end
end)

local equiped = false

script.Parent.Equipped:Connect(function()
print("Equipped")
equiped = true

end)
script.Parent.Unequipped:Connect(function()
equiped = false
end)
--Reload Script
UIS.InputBegan:Connect(function(input)
if input.KeyCode == Enum.KeyCode.R and equiped == true then
print("RELOAD")
game.Workspace["Pistol Reload Sound"]:Play()
reloading = true
Ammo = 32
wait(1.5)
reloading = false
game.ReplicatedStorage.AmmoInMag.Value = Ammo
end
end) -- Thats all my code

[mild peak]

could you provide more information? what's the error message? does it show you the line where it goes wrong?

[leaden carbon]

it's probably the while loop

try to provide more information