Thanks for reporting. I changed this issue from bug to question because it looks like an incorrect usage of the move event. This is by no way meant as criticism, data entry can get quite complex and we only recently had an introduction meeting.
There are 2 issues:
1) Move events should only be used if 2 places are involved
If it's about e.g. a stay in Constantinople an activity event with one location (Constantinople) should be chosen (instead of a move event with from and to location Constantinople).
Fix for existing entries: If it is not a move event, e.g. a stay somewhere you would have to create a new activity event instead and than delete the move event. Sorry for the inconvenience but it is not possible to change the event class after creation because of different link classes.
2) If it's a "real" move event between 2 places you link an actor in the actor tab, e.g. Stephan Gerlach as an participant or enter him in the event form at the person field but not both.
Usually it would be the first one (link via actor tab) because adding someone in the person field at an event would mean "was moved by" an event, e.g. a prisoner transport.
Fix for existing entries: remove the actor at event/edit from the person field.
I hope this explanation is sufficient. We will think about improvements like e.g. update the manual (https://demo.openatlas.eu/static/manual/entity/event.html) to explain it better or prohibit to add the same person in both ways (link in tab and add to person when updating the move event) in the user interface.
Please feel free to ask follow up questions or, in case this is solved, set the status of this issue to closed.
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