If the error message says there is a paper jam that is not visible, HP provides an app (HP Support Assistant) to help with troubleshooting. You can also use it to chat with a virtual agent. Download the app from HP's website at the link below:
[link|https://support.hp.com/us-en/help/hp-support-assistant|HP Support Assistant|new_window=true]
If that doesn't help fix the problem, HP also provides an online form for out-of-warranty printer repair services. You can submit the form at the link below:
[link|https://www.hp.com/us-en/campaigns/out-of-warranty/contact.html|Commercial Printers Out of Warranty|new_window=true]