Have you tried JoseLuis, the administrator?
He has had many dealings with Gasnatural who seem to ride roughshod with installations without permissions.
Are you on a main community street or an internal private to 3.2G street?
Where we have had some previous issues with this company, it has come down to the home owners house insurance company to take up the cause.
(I'm in Cornwall now for the winter, but I was president for 6 years so have dealt with this previously. If you want to PM me, we could talk on the phone.)
My sympathies for the hassle you have.