Daily Mangenta toner cartridge Decrease 10% of versant 80

Dear,

I have one versant 80 and I always print black and white by this printer but Daily Mangenta toner cartridge Decrease 10%. I checked the connection between the MCU PWB and the Toner Crum PWB , Replaced toner CRUM, CRUM PWB, also Replaced all Drum cartridges, and put all NVM default value but problem not solved.

So please support us as soon as possible.I await for your positive response.