The renewable energy supplier was found to have incorrectly charged customers and failed to adequately update the Priority Service Register for vulnerable users.

These failings between 2013 and 2019 impacted more than 115,000 customers and energy regulator, Ofgem, has confirmed it will pay £1.5m – made up of refunds, goodwill payments and redress.

As part of Ofgem’s compliance work, it found that incorrect charges were applied during contract renewals and incorrect VAT rates were applied to certain charges levied to customers.

Further, incorrect cheapest tariff messages appeared on customer communications, several customer payments were allocated to the wrong accounts and iSupply incorrectly recorded customer statuses which affected the Priority Service Register and vulnerable customers.

Ofgem said iSupply had “insufficient governance and processes in place to prevent and swiftly address non-compliance, which resulted in a range of issues that ultimately caused consumer harm”.

While iSupply has confirmed it has improved its governance and processes, the redress package includes:

• Direct customer refunds totalling £809,220.41
• Customer goodwill payments totalling £595,290
• A payment into the Voluntary Redress Fund totalling £95,489.59.

Ofgem confirms this is a separate issue to the £1.5m it was forced to pay in December 2019 also relating to overcharging issues.

In March, iSupply’s parent company, Vattenfall, reached an agreement with EDF to transfer energy contracts to them.

An iSupply spokesperson, said: “iSupplyEnergy always endeavours to act with our customers’ best interests in mind. Earlier this year we identified shortfalls in our service levels and worked hard to put this right for impacted customers. We recognised the seriousness of this situation and agreed with Ofgem to pay £95,489.59 into the Energy Industry Voluntary Redress Scheme. We’d like to offer assurances that all affected customers have been reimbursed with any detriment and a goodwill gesture offered, along with a full and sincere apology.

“The maturity of our compliance capability has grown over time with investment in training, resources and governance. Our leadership team continues to focus on ensuring management of our customer accounts is in line with Ofgem’s license conditions until the customer migration to EDF is concluded in a few weeks’ time.”