https://www.epo.org/en/node/life-circle-validity-activation-renewal-8

Can I use my smart card for signing documents if I have changed my name and the smart card still bears my old name?

Documents submitted in proceedings before the EPO must be signed (Rule 41(2)(h), Rule 50(3) EPC). In both Online Filing and OLF 2.0, a text string signature may be used, that is to say a  string of characters, preceded and followed by a forward slash (/), selected by the signatory to prove their identity and intent to sign. The use of a signature in the form of a text string signature is sufficient to meet the above-mentioned signature requirements. The fact that the smart card used to access OLF 2.0 or Online Filing bears the user's former name does not affect the validity of a text-string signature indicating the user's new name.

In principle, therefore, a discrepancy between the name in the text string signature and the name indicated as the holder of the smart card does not have any procedural consequences.