librewriter stopped working; tried to “repair” and didn’t work; then uninstalled and then reinstalled libreoffice and still is not working?
If LibreOffice Writer stopped working due to a corruption of your user profile - reinstallation won’t help, since this procedure doesn’t affect the user profile. Since you did not mention your operating system, the only general advice to use Safe Mode could be given and to test whether LibreOffice starts in Safe Mode. If that works, reset your user profile.
Reinstalling does not clean the user profile. A corrupt user profile may lead to instabilities and the program not starting. The exact way of restarting your user profile depends on your operative system. Please, read the linked article for more details and if you have any problem, edit (do not use an answer for that) your original question to add more information, such as operative system, LibreOffice version, steps you tried, etc.