How do I reset password in order to change transactions on old invoices?

Greetings, @ops2.

I have just the steps you'll need to reset that password. Please note that only Company or Master Administrator users can edit the Closing date password. See the instructions below to get started:

How to Change the Closing Date Password

1. From QuickBooks Online, click the Gear icon (⚙) and select Account and Settings.
2. Navigate to the Advanced tab and click the Accounting section to edit it.
3. Enter a new password in the Closing date field.
4. Click Save > Done.

This information is also available from our detailed guide on changing the closing password.

With these steps, you'll have that password changed so you can edit old invoices at will. Please know that you can always reach me here for all of your future QuickBooks needs. Thanks for coming to the Community and have a wonderful rest of your week.