Trying to make a Keypad system not working?

So I have a game and i'm trying to make a secret room, that is activated with the correct keypad, but whenever i press the button in the surfacegui, it replaces the current text with number, even though the code is suppose to be multiple digits. I'm not going to list every number button, so here's #1:

script.Parent.MouseButton1Click:Connect(function()
	script.Parent.Parent.TextBox.Text = .."1"
end)

This TextBox and TextButton are in a surfacegui inside a part, and the local script in inside of the textbutton.

Replace the textbox with a textlabel.