Need some help to solve a problem, my L 26500 was printing swatches finished one then stopped showing an error of the first three ink cartridges missing (M,Y,B). Tried rebooting etc. and reinstalling the cartridges but it won't acknowledge them. They are all more than 75% full. Any ideas as to why 3 cartridges suddenly got "lost" by the printer? Anybody else had this problem. Any help or pointers gladly accepted