Popup Error "Not ADMIN"

Ok so i want to make it so if u press an admin command that i have
already coded and your NOT admin i need a popup derma thing saying
“your not admin” <<< all i need is that popup thing


iv looked at that but… its all buttons and drop down menus
no just text

if !ply:IsAdmin() then
local NotAdminPanel = vgui.Create("DFrame")
	 NotAdminPanel:SetPos( 50, 50)
	 NotAdminPanel:SetSize(150, 50)
	 NotAdminPanel:ShowCloseButton( true )
	 NotAdminPanel:SetVisible( true )
	 local ErrorMessage = vgui.Create( "Label", NotAdminPanel )
ErrorMessage:SetText( "Your not admin" )
ErrorMessage:SetPos( 50 , 50 )

I hope this helps, if not feel free to post.