Origin Energy is being taken to court by Victoria's independent services regulator which says the company failed to support more than 30,000 vulnerable customers.
The Essential Services Commission filed the civil case in the Victorian Supreme Court, claiming Origin failed to meet its obligations under the life support and payment difficulty frameworks.
It's alleged Origin did not provide payment assistance or give customers clear information about their entitlements to payment assistance.
More than 30,000 customers were allegedly affected by the breaches between 2019 and 2023.
The commission claims another 11 customers who either use life support equipment or have a person at their home who does, were also failed by Origin.
It's alleged Origin failed to adequately record, update or maintain information on the life support register and provide relevant information to energy distributors.
The alleged breaches put life support customers at increased risk from power interruptions, the commission said.
The independent regulator is seeking civil penalties and other remedies, including adverse publicity orders.
Origin executive general manager Jon Briskin said the company self-reported the breaches and co-operated fully with the commission's investigation.
"We have fixed the IT problems that caused the breaches and, where appropriate, we have proactively contacted the affected customers and provided compensation," he said in a statement on Friday.
"We take very seriously our obligations to support and protect vulnerable customers and we will continue to focus on supporting our customers."