Case C-140/22, mBank (Consumer declaration): Judgment of the Court (Ninth Chamber) of 7 December 2023 (request for a preliminary ruling from the Sąd Rejonowy dla Warszawy — Śródmieścia w Warszawie — Poland) — SM, KM v mBank S.A. (Reference for a preliminary ruling — Consumer protection — Directive 93/13/EEC — Unfair terms in consumer contracts — Article 6(1) and Article 7(1) — Effects of a finding that a term is unfair — Mortgage loan agreement indexed to a foreign currency containing unfair terms concerning the exchange rate — Nullity of that contract — Claims for restitution — Statutory interest