ERR_ILLEGAL is an error from the Epson printer software. It means the printer refused the print request. It usually clears when the printer is reconnected.
Fix it
Check the printer is on, has paper and the cover is closed.
Turn the printer off, wait 10 seconds and turn it on.
On the Master POS, open the printer list. Turn the printer's switch off and on again.
Tap the gear icon and tap PRINT to test.
If it still fails, remove the printer from the list and add it again.
What you should see: a test print and no ERR_ILLEGAL message.
If something goes wrong
Send us the printer model, a photo of the error and the Device Register Code.
Need help?
Email support@nomni.ai or message us from the chat in Nomni Console. Tell us your venue name, the device and what you have already tried.