Hi, @jodibob. I'm here to help.

When printing a check stub with 20 bills attached, I recommend selecting a voucher check in your print settings. These checks are usually longer than a standard check but have the same width. By doing this, you can print all the 20 bills on a single check.

1. Go to your check transaction. (In case you need to look for the transaction, you can use the magnifying glass icon)
2. Click on Print Check.
3. Select Print Setup.
4. Choose Voucher.
5. Select Yes, I'm finished with setup.
6. Reprint the check.

Here's a sample voucher check with more than 20 bill payments: 

If this isn't possible at the moment, there is a way to print the list of bills that were paid on one check. I suggest running and printing a Bills and Applied Payments report. Here's how:

1. Go to Reports.
2. Type "Bills and Applied Payments" and select it. 
3. Choose a time period and apply the appropriate customizations.
4. Click on the Print icon.

For further details about printing a check, please refer to this article: Print a check in QuickBooks Online.

I'll also add Step 3 of this article in case you encounter printing alignment issues while printing your check: Fine-tune the check alignment.

As always, you are welcome in the QuickBooks Community should you have further questions about printing checks in QuickBooks Online. Take care.