The top of the document shows “read only.” I want to edit the document and cannot.
Sometimes if LibreOffice marks something as Read Only you must use Save As… and use another filename, for example Filename - new.odt or Filename1.odt so that LibreOffice tells them apart. Then when you open the newer editable document, you can just delete the old one and use the old filename again.
This read-only mode may happen in some “cross-access” circumstances. I often get it when I open a document created by another user (but group permission allows me to open it). In this case, the warning banner has an Edit Document button in recent releases. Pressing the button clears read-only.
The most frequent case is abnormal termination of a previous session which leaves lock files behind. If you are sure nobody else is using the while at the same time (which is the case on a personal single-session computer), you can try removing the stray lock files. Their location is OS dependent (you didn’t mention which is yours, nor LO version).
In my Fedora Linux, they are at ~/.config/libreoffice/4/. You can get a hint looking at Tools>Options, LibreOffice>Paths and considerinf the “prefix” in AutoCorrect, AutoText or Backup.
Otherwise, do as @LilZebra suggested, save the file under another name. However, this does not solve the issue if you rename it to the original name.
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