Normal odt files that printed fine now do not print at all. The printer only feeds blank paper. The printer will print from other programs. Only program affected is Libre. We had a previous version of Libre when this problem started. I used apt-get purge to remove it and put it back in. Then I updated the program to 6 using the ppa. Still same problem. Any suggestion would be appreciated. The printer has also been taken out and reinstalled just in case it is the problem. All cups programs are loaded. In short I have redone everything I can think of but still no joy.
If you look at Tools > Options… > LibreOffice Writer > Print, are all the correct options “ticked”? And would it be worth asking on AskUbuntu.SE, although they’ll probably say to ask here. 
I finally realized that since the printer would not print any black from any computer, but would print colors, it had to be a black ink problem. Then I remembered that the little nozzle in the bottom of the cartridge holder in an Epson printer can become clogged with ink. I had this problem once before with one of my other Epson printers. I took out the black cartridge, laid it to one side, put on my husband’s headlight and went to work with Qtips and non-acetone nail polish remover. It took two Qtips to clean it. I took two more and dried it off. I put the black cartridge back in and printed both in all black text and in a mixture of black and colors. Feel a little foolish because it took so long to find the problem but was thrown off the track by the fact that the problem started at the same time the Writer program was updated. It is all OK now.
Good to know how you solved it - thanks for telling us how it worked out!