A new page could not be inserted because the page being paginated into does not have a master applied

This is displayed because EasyCatalog is trying to paginate into a page that does not have a master applied ([None]). For example this could happen if there was three pages in a document and page one has the master applied to it, but pages two and three have [None] applied to them.

When paginating an empty document it is best to make sure that there is only one page in the document and that the master has been applied to this page.
Error 2 - EasyCatalog Pagination Module