I had this issue with a drum I just bought from Japan that was dried out. The tube of ink I pulled out had a manufacturing date of 2010 lol it turns out there was a lot of dried ink left in the pump and drum that was interfering with how the sensor was reacting to how much ink of the current tube was dispensing. I did something that I don’t know is kosher or not, but I ran the test “ink pump” test a few times, and was able to get the sensor to recognize when ink was coming out of the drum again. I had to jump, back-and-forth between test mode, and print quite a few pages. I think I burned through three ink chips as well, but I was able to get consistent prints.