Hi @hughesnatalie,
Welcome to HP Forums, this is a great place to get support, find answers and tips.
Thank you for posting your query, I'll be more than glad to help you.
I understand that the faxes on your HP Officejet Pro 8620 e-All-in-One Printer are printed in reverse order.
This issue could occur if the page order is set as back to front instead of front to back
Let's go through a few steps to troubleshoot this issue.
And here's the step by step guide for you in the links below:
1. Print Driver Settings Guide (Windows)
2. Print Driver Settings Guide (Mac)
Let me know how this works.
You have a good day ahead.
Rainbow23
I am an HP Employee
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