I’ve noticed on two different accounts that they both suggest on Page 3:
Good news — you're on our cheapest tariff. We'll let you know if this changes.
Carbon offset gas
You could save £24 (£72 on other account) a year by changing to '100% Green 12m Fixed'. This is currently our cheapest fixed 12 month tariff.
To change your tariff, tap 'Tariff and usage' in your account — it'll take two minutes.
However, both accounts already state on Page 2 that the tariff is: 100% Green 12m Fixed
Seems like the promo is erroneously suggesting changing gas to an already active tariff! It doesn’t suggest changing the electricity.