I am on my third Canon Pixma printer; a couple of times I had the same problem with the print head, dried ink clogged the heads and the cartridge ink would not flow through. I just removed the print head, and gave it a strong cleaning. I held it under a flow of very warm water (not too hot to the touch) and gently pressed a paper towel on the screens. I then lightly dried with a paper towel and let it sit for several hours to thoroughly dry, and then reinstalled. If the problem is a clogged print head, this will fix it. Just make sure it is thoroughly dry, especially the electrical contact circuit board, before reinstalling.
In addition, if you take each print cart out and gently wipe the nozzle with alcohol on a paper towel, that should free up the nozzle again. But if the ink is just too heavily caked on the nozzle that may not work. It would be very unusual for all your carts to stop working at the same time.
If the above does not work, probably the print head has failed. It would probably cost you almost as much to replace it as to buying a new printer, and that is only if it is even available. If the printer is older most likely not.
I have used LD Ink for years, and only had one bad cart from them, which they replaced immediately on one phone call. Their ink and carts are every bit as good as OEM equipment, and I have never had a problem with them. And....I do a ton of color printing.