Origin Energy (ASX:ORG) paid a total of AU$135,600 to the Australian Energy Regulator due to alleged breaches of overcharging rules, the regulator said in a statement Thursday.

The energy firm allegedly failed to inform two customers within 10 business days that they were overcharged AU$4,317 and AU$2,885, respectively, violating the National Energy Retail Rules, the regulator said.

The alleged breach was uncovered after a regulatory investigation was conducted when Origin self-reported that breaches may have been made during its transition to customer management system Kraken from SAP, the regulator added.

"We understand retailers periodically need to undertake major IT upgrades and that mistakes can and do happen, however, retailers need to have a plan and sufficient resources in place to protect their customers by ensuring they detect, remedy and self-report mistakes as soon as they can," said AER Deputy Chair Justin Oliver.

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