it has never failed before. I’ve never had to sign in to libre office before, either. What prevents the documents from opening?.
libre office6.2not opening
prevents the documents from opening
What now? These are two different things and most probably require different solutions.
I’ve never had to sign in to libre office before
There is no sign in to LibreOffice. Probably you don’t tell us in addition that you are using some external, network based storage (cloud, nas server, …), which may require a login.