I have a Dell V525w inkjet printer that was printing double sided pages from my Dell XPS 13 laptop (Windows 10) and Dell Inspiron 531 (Windows Vista) using a wifi connection without a problem.  Then all of a sudden, it stopped.  For both computers. I have tried updating printer and PC drivers but they had no effect. as far as I can see, all the settings are correct for two sided printing. I have uninstalled it and reinstalled the printer also without success. Any suggestions?

Update to my post:  I think my problem is solved.  I left the system for a couple of hours and discovered that a new (second) printer icon had been automatically installed with a 14 number and letter description.  This had been installed usin a WDS port. I had previously installed the printer using its IP address which went onto TCP/IP port. I can now print duplex using the new icon.