A method for authenticating a user at and reporting about a use of a charging device using an authenticating and reporting system, the method comprising the steps of: - generating at least one first single-use encrypted authentication element in a database unit, wherein the single-use authentication element is configured to grant an access for the user for a charging procedure on a designated charging device; - transferring the first encrypted authentication element to the charging device via a first mobile device; - decrypting the first encrypted authentication element in the charging device; - validating the decrypted authentication element to initiate a first charging procedure in the charging device; - generating a first charging report element in the charging device after ending the first charging procedure; - storing the first charging report element in a storage module of the charging device; - transferring the first charging report element to the database unit via the first mobile device or another mobile device; and - providing a second single-use encrypted authentication element to the user only after processing the first charging report element in the database unit to thereby restrict a further access until the first charging report element is returned to the database unit, wherein the first and second single-use authentication elements are single-use tokens, characterized in that wherein the first and second authentication elements, each comprises: - a charging device identification parameter, - a user identification parameter, - a sequence parameter, and - a confirmation timestamp of a charging report element, wherein generating a first charging report element in the charging device comprises generating a first encrypted charging report element, wherein validating the decrypted authentication element comprises verifying whether the sequence parameter of the decrypted authentication element is higher than a last sequence parameter stored in the storage module of the charging device, and wherein once the encrypted authentication element is presented to the designated charging device, the charging device decrypts it, verifies a signature, and checks the sequence parameter against a local table of users and last-stored sequence parameters. - generating at least one first single-use encrypted authentication element in a database unit, wherein the single-use authentication element is configured to grant an access for the user for a charging procedure on a designated charging device; - transferring the first encrypted authentication element to the charging device via a first mobile device; - decrypting the first encrypted authentication element in the charging device; - validating the decrypted authentication element to initiate a first charging procedure in the charging device; - generating a first charging report element in the charging device after ending the first charging procedure; - storing the first charging report element in a storage module of the charging device; - transferring the first charging report element to the database unit via the first mobile device or another mobile device; and - providing a second single-use encrypted authentication element to the user only after processing the first charging report element in the database unit to thereby restrict a further access until the first charging report element is returned to the database unit, wherein the first and second single-use authentication elements are single-use tokens, characterized in that wherein the first and second authentication elements, each comprises: - a charging device identification parameter, - a user identification parameter, - a sequence parameter, and - a confirmation timestamp of a charging report element, - a charging device identification parameter, - a user identification parameter, - a sequence parameter, and - a confirmation timestamp of a charging report element, wherein generating a first charging report element in the charging device comprises generating a first encrypted charging report element, wherein validating the decrypted authentication element comprises verifying whether the sequence parameter of the decrypted authentication element is higher than a last sequence parameter stored in the storage module of the charging device, and wherein once the encrypted authentication element is presented to the designated charging device, the charging device decrypts it, verifies a signature, and checks the sequence parameter against a local table of users and last-stored sequence parameters.