This is an often-requested feature in Finale - there is no way to reset custom line-by-line chord baseline adjustments. (There should be.)
Although Finale doesn't supply a method to remove all line-by-line baseline adjustments, there is a workaround I just tested, and it works.
Export the document you need to fix as xml.
Import the xml. The chord positioning will look as it did previously -
but then, select all, and go to Utilities/Change/Chords and add some value (start with zero) to the Default Position. (this option is hidden in a dropdown in the middle of the Change Chord dialog box).
This does the trick. All the chord baselines will be reset to the baseline default you define.
MacOS Sierra, Finale 25.3