I received this from Good Energy when I asked about closing my account:
Looking at our records, your most recent bill includes your final electricity reading, provided to us by Bulb at the end of December. However, we haven’t received a request for your gas to leave us, which is why your account is still open. If Bulb have taken a gas supply for you, please ask them to check what supply number they have taken. To confirm, the supply number for your gas with us is 1024351003, so this should be the one that they’ve requested. If they have another number, they may have taken an incorrect gas meter in error.
Can you confirm you’ve taken the right supply number and also that the switch for my gas account is underway?