I have four custom price lists which each override one or more of my standard prices.

Today, none of the custom price lists contain anything, and I'm unable to edit them.

If I first create a NEW price list, then I am able to edit the four existing price lists, BUT, none of the four custom lists contain the prior overrrides.

When I override a  price in any list (including the new one added today) that price now shows in ALL five lists.