Provide option for organisers to upload a list of blocked user emails and names

[mariobehling]

Some events have a list of attendees they do not accept at their events, e.g. because of CoC violations. Implement a feature to add a list of user emails and names that will not be able to register for the specific event.

[AviGawande]

Hello @mariobehling for this issue, we could take the blacklisted users at the event settings and thereby restricting those users from initial registrations.
please let me know, what are your thoughts on this.