If you go here click here and put in your product number it should take you to your product.
I went through it and got to here which says
If you have replaced the color cartridge with new cartridges and are still having the problem, the printer may need to be serviced. Contact HP for assistance in resolving the problem
Go here for their numberclick here
It is 0870 010 4320
except for Bank Holidays
Calls are charged at 8p per min.
This sounds like your best bet.
You can first see if you need to update the drivers etc from their site but I think you will be better phoning.
They are very good as I have done so in the past.
Hope this is helpful