Black ink not working.

[DavideIo]

hello,

I tried to  make a black photocopy but it turned out light grey

I also tried to print the diagnostic, here is the scan. 

Like you can see the colors are "fine", but the black component is almost missing.

the behavior is the same if I print by my android smartphone or if I photocopy directly from the printer

From the app the level are 100% for both cartridges, which are 5 months old (but is happening from a couple of months) and have printed less then 50 pages, so it shouldn't be the problem (they are original HP from the Instant Ink program)

thanks

[Riddle_Decipher]

@DavideIo Thanks for sharing your concern with the HP Community,

here's what I'll need, so I may be able to provide an accurate solution:

What is the product number of your device? Use this link to find it: click here

(Ensure you do not share any of your personal information such as serial, phone number, email ID, etc.)

Have you attempted any steps on your own before posting on the HP Forums?

When was the last time it worked without these issues? 

Please reply with the details for further assistance.

Eager to help!

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