Select merged set -> edit -> fix track grouping (all albums selected) -> DOES NOT REMOVE THE MERGE!!
did you highlight the tracks you want to unmerge and select Remove.
No, but I do not want to remove the track, only correct the old typo.
Correction - that above reply of mine was not on topic, apologies for any confusion.
I accidentally merged albums inappropriately and understood the undoing of the merge was from “fix track grouplng” but that does not work so advice please on what I should be doing.