Cannot edit existing leadership position

I drill down to a scout, select leadership and see an existing position which I want to edit. In theory I should be able to click it and enter things like the ending date, but it goes sort of 404 on me.

@FrederickNorthrop - I trust you are NOT doing this in scoutbook.scouting.org. All of that should be handled in advancements.scouting.org

The ONLY things left in legacy scoutbook are mbc tools and payment logs.

this is where you should be