EBU Single Rulebook Q&A 28 June 2018 2018_4041 Display of incorrect authentication factors in case of failed authentication attempts

For remote card transactions, may the user be informed of the incorrect authentication factor in case of a failed authentication attempt provided this does not increase the risk of fraud (e.g. for in-app transactions)? Article 4(3)(a) RTS requires that, if the authentication has failed to generate an authentication code, the identification of the incorrect authenticating factor must be impossible.