Using OpenOffice? Getting messages like "This document was created by a newer version of OpenOffice"? If so, the document was probably created in LibreOffice, a successor project with many extra features and updates. LibreOffice 7.0 introduced ODF 1.3, an updated document format: https://blog.documentfoundation.org/blog/2020/11/20/what-to-do-with-a-document-created-by-a-newer-version-of-openoffice/