Hello, ME2020SH.

When printing a invoice, the information will depend on the set up from the Standard template. I suggest going to the Custom form styles section to configure the setting and show the missing columns. 

Here are the steps:

1. Click the Gear icon in the upper-right corner and select Custom Form Styles.
2. Search for the template with the Master form type.
3. Choose Edit. 
4. Go to the Content tab.
5. Hit the pencil icon in the upper-right corner.  
6. Put a check-mark on the box and enter the PO number.
7. Tap Done. 

From then on, you can now enter PO numbers on your invoice transaction and information will now show when printing it.  

However, If the same thing happens, I suggest running QuickBooks Online (QBO) in an incognito or private window. This mode is free from cache files that avoid unexpected behavior when printing it. This way, we'll know if this is caused by browser issues.

You can press Ctrl + Shift + N in Chrome and if you're using Firefox, press Ctrl + Shift + P. Once logged in, please proceed with printing the transaction to view the result.   

If this works, I recommend clearing the browser's cache to keep its memory updated. It also improves performance and fixes internet bugs. Alternatively, you can use other supported browsers to run QBO.

For additional information, I've attached an article you can use to customize the Standard template further in the: Customize invoices, estimates, and sales receipts in QuickBooks Online. 

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