Judgment of the Court (Grand Chamber) of 9 April 2024.#FY v Profi Credit Polska S.A. w Bielsku Białej.#Request for a preliminary ruling from the Sąd Okręgowy Warszawa-Praga w Warszawie.#Reference for a preliminary ruling – Principles of EU law – Article 4(3) TEU – Principle of sincere cooperation – Procedural autonomy – Principles of equivalence and effectiveness – Principle of interpreting national law in conformity with EU law – National legislation providing for an extraordinary remedy allowing the reopening of civil proceedings closed by a final judgment – Grounds – Subsequent decision of a constitutional court declaring that a provision of national law on the basis of which that judgment was given is incompatible with the Constitution – Loss of the opportunity to take action on account of a breach of the law – Broad application of that remedy – Alleged infringement of EU law resulting from a subsequent judgment of the Court of Justice ruling under Article 267 TFEU on the interpretation of EU law – Directive 93/13/EEC – Unfair terms in consumer contracts – Default judgment – Failure of the court hearing the case to ascertain of its own motion whether contractual terms are unfair.#Case C-582/21.