The council could create the contact database or third-party database to collect the identifying and contact details of the individuals it relates to. The incorporation in this third-party database of the data of the Register of entry and exit of documents would not be compatible for the purposes of using the data contained therein for subsequent notifications, but instead it could be to use the identifying and contact data in other procedures of an analogous nature. In application of the principle of accuracy, the city council must take the appropriate measures to collect the different addresses or electronic means that the citizen has chosen for each procedure to receive administrative notifications or whatever is relevant in accordance with the applicable regulations. The data that make up the third-party database may not be retained beyond the retention period applicable to the purpose for which it was collected, must be kept up to date and the affected persons must be informed.