The Issues Conflict Message Box
This error box appears when there is no way to produce a valid change package entry for an element by combining your new set of changes with the existing change package entry. The requirement that the basis version must be an ancestor of the head version cannot be fulfilled.
You can remedy this situation by performing a merge at the element level. (There is no merge operation defined for change package entries.) In the example above, merging version H and version X would create a new version; a change package entry with the new version as its head can be combined with the existing entry.