Hello,
This is currently a know bug and will be fixed on the next update. You could temporary disable the consent box:
Which is located under Events > Settings > Privacy > Consent, by setting all the forms to ‘Do Not Include’
I have the same problem which occurs when submitting an ordinary event and when I am adding it while logged in as admin so hope this is sorted out in the next update as it also prevents the creation of the event if attempting to add a new location. The location is created as ‘pending’ and have to go to the locations section to approve it then back to the listing to publish it.
you can try the latest EM version 5.9.4