if the print quality is still acceptable, reset your drum unit by sticking on our reset chip. The procedure is very easy, takes 1 minute, full instructions are provided.
The chip will not fix any print defects, or improve print quality, it simply resets the drum unit back to zero so you can continue printing.
One chip required per drum unit. Chips can only be used to reset one drum unit.
http://www.zinetic.co.uk/intec_cp2020_drum_reset_chip-details.aspx