Some team members unable to see a library or update a library with changes.

I'm working for a large organisation who are using XD across design teams to centrally manage templates and libraries.

We seem to have a a couple of problems which randomly effect team members.

Major issues are

1) Can accept a invite to a library and see that library on the Web version of CC. However that library or file will not show in the CC Desktop App or within the libraries panel in XD.

2) Someone who has access to edit the XD file that controls a Library cannot publish changes to that library. They try to update the library and get an update error. There does seem to be an active connection as the document is still auto saving.

Sometimes it seems to make the change but its not visible to other library users. Sometimes the update/publish button just doesnt show.

I'm guessing it may be a Synching or connection issue but it doesnt effect all team members who are using the same interent connections and systems.

Any ideas?