Thijs With residence permit I meant the ID card that foreigners get in EU countries. It should be enough in most cases, my foreign friends with bunq accounts just needed to their German residence permit card (looks the same as an ID card) to go through verification.
So if the OP is living in Bulgaria with Bulgarian citizenship: They should use their passport, because regular Bulgarian ID cards aren't accepted.
If the OP is living in Germany with Bulgarian citizenship: As a foreigner they get a residence permit card from Germany, which they can use for verification. They don't (normally) need any of their documents from Bulgaria.
