Hundreds of Octopus Energy customers who adjusted or lowered their direct debits after the energy bill discount scheme ended have been hit with higher than expected bills.
The £400 energy discount scheme - split over six months into payments of £66 and £67 - came to an end this month.
The scheme began in October and for Octopus customers paying by direct debit, they had the discounts automatically applied to their bill each month, rather than as a cash refund into their bank accounts.
But for some customers who chose to adjust and lower their direct debits from this month, in anticipation of the scheme ending, the £67 has been added on top of their new monthly payments.
This has left some people with bills that are much higher than what they were paying even before the discount came into place.
Customers who did not adjust their direct debits had the £67 applied to their already discounted bill, essentially taking them back to what they were paying before the discount.
Octopus said it was not a widespread issue and that "hundreds" out of its 3.1 million customers may have been impacted.
The energy firm said the issue only affected those who had pre-empted the rise and adjusted their direct debit before the £67 was added.
One person, who wanted to remain anonymous, told The Mirror she had been paying £88 before the energy discount came into place in October - this then reduced her bills to £21 with the £67 rebate taken into account.
Before the scheme came to an end, she adjusted her direct debit to £75 - but was shocked to find the £67 was added to her bill in April - bringing it over £140 and way above what she was paying before the discount.
Other customers who were impacted took to social media to share their frustrations.
One Twitter user said: "Hi, you sent me my monthly bill for £117, I am already £208 in credit, I reduced this month's DD payment to £50 but you still collected £117. Why?"
Octopus Energy customers are able to adjust their direct debits as and when they please through their online account or over the phone to reflect their usage.
The energy firm says it makes sure its customers are "always in control".
However, some of those affected have reported that the issue has affected their finances for the rest of April with some reporting that their other bills had been impacted.
One customer said they were one of the "lucky ones" as they had enough in their account to cover the unexpected bill however others could face serious repercussions of this.
They tweeted: "However, if this is widespread then not all will be as fortunate, and many will experience their Direct Debit payments bouncing - something that many banks charge for - This needs sorting @OctopusEnergy."
One Twitter user said the automatic approach was "lazy" as many used the feature to budget their spending, whilst another asked: "Why have they even got the button to amend if they were just going to take it anyway??".
Octopus said it told customers about their approach initially and had sent an update before the new direct debits were sent out.
They also explained that those who made changes after their bill arrived would not be able to benefit in April as their bank would not "have enough time to process the change".
Customers who have been affected can contact the firm to ask for a refund or money off future bills.
If you have been affected by this issue specifically, you can email Octopus Energy at governmentsupport@octopus.energy and they will assist you going forward.
A spokesperson said: "Unlike many energy companies, Octopus lets you amend your direct debit online.
"Banking processes mean that changes close to a payment date may not go through in time for the next payment, but the one after that.
"This month, timings were very tight as we set payments later than usual following government support scheme changes on March 15.
"If this has caused any incorrect payments, we are delighted to help customers with a refund of the difference."
