The Director may authorize in writing, a refund, credit, or adjustment of any amounts when he/she determines that an error, miscalculation, or mistake has occurred which affects any ratepayer(s). The nature of the error, miscalculation, or mistake should be documented together with the steps taken to prevent future occurrences. No refunds, credits, or service charge adjustments may be authorized pursuant to this Section unless brought to the attention of the Director within three years of the occurrence of the error, miscalculation or mistake.