Gas meter not changed out of Gas

I have changed over to Bulb a few weeks ago and had the meters changed from prepayment to normal meters, the Gas meter, however was not changed and I have now run out of credit on the previous meter even though I have paid in advance with Bulb… I now have no Gas and no way to contact Bulb to sort this out and have been without hot water for 3 days so far as I thought it was a boiler issue initially but now know its a supply issue. I was told everything had been sorted out weeks ago and and I had nothing to worry about so did not give it another thought.