The cartridges have been installed in the printer for a long time and the ink is not in optimal condition. The manufacturer recommends using the cartridges within 6 months after they are installed in the printer. We will have to replace them with new ones.
If your printer is an EPSON EcoTank, on some models you have to reset the ink levels in the printer after filling the tanks:
Access the menu Settings – Maintenance – Reset ink levels