Hi, I believe that a printer cartridge needs to print just a couple of lines of text at least every two weeks just to keep the ink flowing and to stop the nozzles in the print head from drying out.
I would suggest standing the cartridge print head in about 1/4" of hot water in a saucer (not boiling) for about 10/15 minutes and then dab it on to a moist paper tissue until you can see the three colours on the tissue. Repeat the water if necessary.
You could also try ink flush in a saucer.
When you see all colours on the tissue, do a head clean and the re-align the cartridge if required.
If you go back to the suppliers I would think that they would only suggest that you try a new cartridge before doing anything else.
Incidentally, if it is a black only cartridge then you will have to try and judge when all the jets are unblocked.
I hope this is of some help.