That is the problem then, you are not following the proper procedures.
These epson printers are very picky about the replacement process. Replacing the cartridges via any other method can actually cause permanent damage to the printhead.
This is not an automatic process as on some other printers, some menu steps are required prior to physical replacement:
Press the home (house icon) button and select Setup (wrench icon) > Maintenance > Ink Cartridge Replacement.
Lift up the scanner unit (below the glass)
Open the cartridge cover
Squeeze the tab on the cartridge and lift the cartridge straight up to remove it.
Gently shake the new cartridge four or five times, then remove the cartridge from the package, removing the yellow tape.
Insert the new cartridge into the holder and push it down until it clicks into place.
Close the cartridge cover and push it down until it clicks into place.
Select Check on the LCD screen to make sure the cartridge or cartridges are installed correctly.
Close the scanner unit.
If the problem still persists after this, then you damaged the printer when you replaced them improperly before.
There is no quick or simple fix for that, but since it is less than a year old your best bet is to call (800)(###) ###-####/u> to file a warranty claim and ask them to replace it for you.
Though they wouldn't be obligated to cover physical/user damage, they will usually still help you out.
Best of luck to you,