HP Office jet 6700 Premium Printer (Downley HP13)

An amazing printer that has decided to only intermittently print. We Googled the problem and were told to clean the print head (which we did) but unfortunately, the problem remains. As per picture, the print report seemed to print OK. Unfortunately, we've drawn a blank so any techie people out there who think they can resolve the problem, are very welcome to have a go! Collection from Downley. Thank you.