I have deleted all other printers and devices. In the email that contained my key, there is a line that reads: Please, download and install the required Firmware for your Epson model from this link : https://inkchip.net/soft/, however, my printer isn't on the list do download the firmware. When I purchased the key, it said my printer is supported. I have an Epson ET-4700. Is this possibly the reason why it isn't working? What is the firmware for?