Welcome to the HP Forums, I would be happy to help you with your Officejet 8620. I understand you have experienced a paper jam and can not get the tray back into position. Perhaps there is still a small piece of paper inside of the printer preventing the tray from sitting right. Please take a look at the following document as I feel it might help you to check the printer over and get the tray installed: HP OfficeJet Printers - A 'Paper Jam' Message Displays.
Please let me know if this resolves the issue. In fact, if this does resolve the issue, please click the Accept as Solution button below so others can see your issue is solved! If you require further assistance don't hesitate to ask, I will gladly do all I can to help. 🙂
Sunshyn2005 I work on behalf of HP
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