# Recital 88 *In force · Directive (EU) 2015/2366, OJ L 337, 23.12.2015 · Checked against EUR-Lex on 26 Oct 2026 · [Official source](https://eur-lex.europa.eu/eli/dir/2015/2366/oj/eng)* It should be possible for the payment service provider to specify unambiguously the information required to execute a payment order correctly. On the other hand, however, in order to avoid fragmentation and jeopardising the setting-up of integrated payment systems in the Union, Member States should not be allowed to require a particular identifier to be used for payment transactions. However, that should not prevent Member States from requiring the payment service provider of the payer to act with due diligence and to verify, where technically possible and without requiring manual intervention, the coherence of the unique identifier, and, where the unique identifier is found to be incoherent, to refuse the payment order and inform the payer thereof. The liability of the payment service provider should be limited to the correct execution of the payment transaction in accordance with the payment order of the payment service user. If the funds involved in a payment transaction reach the wrong recipient due to an incorrect unique identifier provided by the payer, the payment service providers of the payer and the payee should not be liable, but should be obliged to cooperate in making reasonable efforts to recover the funds including by communicating relevant information.