Why can't I make borderless prints in Lightroom classic when I can do so in Photoshop?

This Spring I bought a new laptop (Dell) and upgraded from Lightroom 6 to Lightroom Classic. Previously, with the same printer (Canon multifunction TR8620) and my old laptop, I was able to print borderless prints from Lightroom 6 without problems. Yesterday, I tried making some prints of my Grandchildren using Lightroom Classic and the same printer. I was unable to make a borderless print in Lightroom. I was using 8 1/2 x 11 Canon photo paper. I had checked the "Zoom to fit" in Lightroom, on "page setup," which takes you to the menu for the Canon printer, I chose borderless print and selected maximum "extension." I was unable to set the margins in Lightroom at zero. It printed as shown on the screen, which produced a narrow white border around the print. I was able to print borderless by right clicking on the photo in Lightroom and selecting "edit in" and "open as a smart object in Photoshop." This opened the picture in Photoshop and I was able to print borderless with no problem in Photoshop. While this is a workaround, it seems unnecessary. What am I doing wrong in Lightroom?