I had a problem with this same dotmatrix printer but eventually the problem was resolved. I don't use the printer often but when I used it yesterday it would not work and the symptoms were similar to my previous posting. I have resolved the problem by deleteing the printer then adding it (or a similar one) back again.
https://forums.mageia.org/en/viewtopic.php?f=24&t=6704
I am using Mageia 3 KDE but the same problem was apparent with Ldre, Xfce and RazorQt.
After starting a print the job is found it was paused. On investigation the printer has become not enabled. Once enabled the printer become not enabled again. In Control Centre-Hardware-printers; I duplicating the printer and deleting the orginal but that did not resolve the issue. But deleting the printer then adding it again did solve the issue.
There has been a few updates since I last used the printer including to the Kernel. (I did try reverting to an earlier kernel unsuccesfully). It is as if there the driver can be put in an undefined mode that can not be cleared?
There are two print drivers that when this issue is resolved work with my LX800 printer;
LPT#1, Generic, ESC P Dot Matrix, EPS9MID or EPS9HIGH.