The consumer should send the meter readings frequently (if possible monthly) to avoid estimated billing.
In the invoices of your supplier, you should find reference to the period for sending your meter readings that depends on the billing period, so you have two options: inform the meter readings to the current supplier or directly to your distributor network operator.

In case your distributor is EDP Distribuição, you can communicate the readings in the Online form of the EDP Distribuição website, through the Line of Meter Readings 800 507 507 (free call and available 24 hours) or through the EDP Distribuição App.