how do i make 3 buttons increase a value?

notes:

• 3 buttons, all have a purpose of increasing the counter by 1 with every press
• if i press button1 the counter increases, but if i press button2 or 3 it goes back down to zero or it stays at 1

all the buttons have the same script

aaa = script.Parent.Parent.BrickCounter
Clicks = 0

script.Parent.Parent.BrickCounter.SurfaceGui.TextLabel.Text = Clicks
function onClicked()
	Clicks = Clicks+1
	aaa.SurfaceGui.TextLabel.Text = Clicks
end

script.Parent.ClickDetector.MouseClick:Connect(onClicked)

thanks in advance