My printer Workforce Pro WF-4820 won't print

First the message was that cartridges were needed. That was done. Now it says there is a paper jam. I have turned it inside out and there is no paper

Short summary:

Check to make sure that your printer is really out of paper. Sometimes, it can be easy to forget your paper levels, and there could be a piece of paper that got stuck in the printer, so it never hurts to double-check.
If you have verified that there is no paper jammed inside, check the printer's sensors. There are two sensors in the back that sense the paper feeding. In the front, you'll have a door sensor, plus one that measures the position of the printhead.
The first sensor in the back is a tray sensor. The paper tray will push the lever on this sensor, mechanically forcing a transfer to the left. Check to make sure that the lever goes forward if you move the tray inward. Notice how the paper jam error message mentions the paper tray—this is why you should make sure that the sensor and lever are working in that area.
If the above steps don't resolve the issue, remove the Toner cartridge and then gently and carefully give the printer a few upside-down shakes. After that, try removing all the cartridges from the printer and reinstalling them one at a time.
If the printer asks for a Print Head Nozzle Check, open the menu on the printer, and find the "Maintenance" tab. Then, follow the instructions to perform the nozzle check.
If the nozzle check is fine, try printing again to see if the issue has been resolved.

Mia Green

Hello, thank you for using Howly.
Have you tried unplugging your Epson printer for 60 seconds, then plugging back in?

Customer Replay

Yes

Mia Green

And you have verified that there is no paper jammed inside?

Customer Replay

Yes

Mia Green

How long have you been able to use your printer before the issue came about?

Customer Replay

About a year

Mia Green

Have you checked for jammed paper in the sideways facing compartment?

Customer Replay

Yes

Mia Green

Can you unplug your printer for 60 seconds and disconnect all of the cords?

Customer Replay

Done

Mia Green

Thank you!
Do you have ink cartridges in your printer?

Customer Replay

Yes

Mia Green

Can you remove them and put them back again?

Customer Replay

Done

Mia Green

Now, please, turn the printer on and check it.

Customer Replay

I removed them, put them back and still get the paper message.

Mia Green

First, check to make sure that your printer really is out of paper. Sometimes, it can be easy to forget your paper levels, and there could be a piece of paper that got stuck in the printer, so it never hurts to double-check.

Customer Replay

Done, with flashlight.

Mia Green

Great!
Once you’ve eliminated the possibility that a foreign object is causing the jam, you should turn your attention to the printer’s sensors. Printer sensors can trigger error messages if they are malfunctioning. Luckily, printers do not contain very many sensors, so you should be able to determine the root of the problem fairly easily. There are two sensors in the back that sense the paper feeding. In the front, you’ll have a door sensor, plus one that measures the position of the printhead.

Customer Replay

And what should I do with the sensors?

Mia Green

The first sensor in the back is a tray sensor. The paper tray will push the lever on this sensor, mechanically forcing a transfer to the left. Check to make sure that the lever goes forward if you move the tray inward. Notice how the paper jam error message mentions the paper tray—this is why you should make sure that the sensor and lever are working in that area.

Customer Replay

There is no change. I'm not sure about the sensors but it pulling the tray in and out didn't change anything.