How could one verify the rectitude of calculations and amounts included in the invoice issued under document on finding breach of contractual terms?

First, the consumer should request the supplier to submit the recalculation. If the electricity consumption has been recalculated under the appliances included in the document, then one should verify if the number of use hours for the appliances included in the calculation matches with the number of hours provided by the table of Annex 4 to the Regulation on electricity supply and use. One should also verify if the power of the appliances included in the calculation matches with the real power of the appliances owned by the consumer. The electricity amount foreseen for invoicing will be the difference between the electricity amount calculated and the electricity amount already invoiced and paid for that period, unless the calculation is done only for the appliances illegally connected by bypassing the measurement device and the use installations. If the calculations are done according to the flat fee system, one shall apply the tariff in force during the calculations.