After a refill of several carts in the 3880, once I closed the lid two showed up on the LCD with an X through them. Some cart error message to.
I found if I wiggled those X-boxed carts on the LCD up and down when sticking out of the printer, the boxed ones with the X would disappear and re-appear on wiggling them. Seems they don’t make solid contact with the gold connectors above the chips in the printer.
I found some scraps of fleece and cut them about an inch wide and three inches long. Put them on the bottom of the metal rail those X carts slide into and hold onto it while you slide the cart in over the tops of the fleece. Helps to make a better contact and the “Wiggle Test” shows no more flickering with the ink cart error message.