My dell a924 printer has a blinking lite and reads ( right cartridge incorrect) and will not print?

I have changed Dell cartridges still get error and the amber lite blinks . and will not printMy dell a924 printer has a blinking lite and reads ( right cartridge incorrect) and will not print?
Make sure it is installed correctly, and that you took the plastic covering off the bottom. If that does not work, the cartridge may be defective.