Judgment of the Court (Fifth Chamber) of 3 March 2021.#Poste Italiane SpA v Riscossione Sicilia SpA agente riscossione per la provincia di Palermo e delle altre provincie siciliane and Agenzia delle entrate – Riscossione v Poste Italiane SpA.#Requests for a preliminary ruling from the Corte suprema di cassazione.#References for a preliminary ruling – State aid – Competition – Article 107(1) TFEU – Conditions under which applicable – Article 106(2) TFEU – Services of general economic interest – Management of the post-office account used for collection of the municipal real estate tax – Undertakings benefiting from special or exclusive rights granted by the Member States – Fees set unilaterally by the recipient undertaking – Abuse of dominant position – Article 102 TFEU – Inadmissibility.#Joined Cases C-434/19 and C-435/19.