Odt Write-protected content cannot be changed. No modifications will be accepted

[Field]

I use LibreOffice Writer 7.3.7.2 on linux.
I have several directories with odt (LibreOffice writer) files.
I have created all these files myself by opening an existing file, modifying the old file and saving the new file with a new file name.
In some directories, I can open and edit the odt files.
In some other directories, I can open the odt files but I cannot edit them. If I try I get the error message:
Write-protected content cannot be changed. No modifications will be accepted

Further observations:
Using the editable odt files, all entries in the menu Form can be selected except
Name
Description
Using the non-editable odt files, many more entries in the menu Form cannot be selected (= are greyed out) like
Clone formatting
Clear direct formatting
Character
Paragraph
Bullets
…
The write permissions of the directories with editable and non-editable odt files are 775 rwxrwxr-x. The non-editable odt files have the permissions 664 (-rw-rw-r–), the editable odt files 644 (-rw-r–r–).
The odt files are files without forms.
The same day, I tried to edit an odt file with forms (XML). This file, I used to create a pdf file with editable forms. I failed to edit this odt file and tried to check and uncheck different check-boxes about
Form _ Design Mode
menu bar Form Controls
menu bar Form Design
Maybe, I unintentionally damaged something.
How can I get rid of the problem not being able to edit
odt files (with or without forms)?

[ajlittoz]

Have you a non-confidential file you can attach to the question? It will be easier to eventually diagnose the issue if it is related to the document (vs. directory/file permissions).

What is your Linux distro? Desktop environment (Gnome, KDE, MATE, LxQt, Xfce, …)?

[Field]

Solution:
Background Linux 5.15
I uninstalled the package LibreOffice-writer 1:7.3.7-0ubuntu0.22.04.7
I purged the computer from remaining LibreOffice-writer snippets by using the package manager inside the Linux distribution (command “purge”).
I reinstalled the same package (same version).
I did not reboot the computer.
I opened a formerly not editable odt file.
And the file is editable again.