It depends where the responsibility for the physical connection of the gas begins and ends. If it’s the supplier side, make a claim to them. If it’s the consumer side,, and you are an owner, make a claim against the owners corp for not maintaining common property … but bear in mind that everyone else can do the same so you may be no better off.
If you are a tenant, make a claim against the landlord for failing to tell the Owners Corp to fix it.
And thank-you for your kind words.