Quite possibly the worst company I've ever dealt with. Ovo (and SSE, who it took over) overcharged me c. £3k between Dec 2021 and mid 2023. I was unable to make any progress with Ovo obtaining refunds (who either delayed, failed to engage completely, failed to understand the issues and flat out denied matters of clear fact). Accordingly, I had to go to the Ombudsman, twice, to seek redress. The Ombudsman found in my favour both times. As yet, Ovo claims it has implemented the Ombudsman's recommendations, yet it hasn't: three months after the decision, it has yet to issue the agree solutions of i) an apology and ii) refunding a the remaining £1315. I have chased repeated, directly and via the Ombudsman, copying widely within Ovo. They have failed to substantively respond. This is causing financial detriment (lost liquidity, interest, etc), stress and a huge amount of wasted time. I am currently preparing legal proceedings. I would strongly recommend that you avoid them at all costs. I have since moved to Octopus energy, who have been the absolutely opposite - extremely helpful and responsive, with excellent customer service.