Same thing here, even in just released version 5.8.4 Viewing actual fields show in proper order. But when editing, within a repeater (and all children repeaters) the fields within reverse order. Top level items don’t reverse (but only testing with one file right now).
With 5.8.3 the order of top level and repeater items would be random, or sometimes simply reversed.
Welcome to the Advanced Custom Fields community forum.
Browse through ideas, snippets of code, questions and answers between fellow ACF users