I'll take it as you're referring to the steps provided by IntuitChris, mgonsalves.

There's another way on how you can reverse an invoice payment. I'll show you how:

1. Click Sales in the left panel, select Customers.
2. Select the name of your customer.
3. In the Transaction List tab, click the paid invoice.
4. Click the 1 payment made link.
5. Click the date.
6. In the Receive Payment page, click More.
7. Click Delete.
8. Click Yes to confirm the action.

I've also added screenshots as your visual guide:

However, if you're referring to the steps inside the link provided by JessH, you can do a basic troubleshooting step. In your phone, go to Settings, and then click Reset App Data.

I'm always around if you still need my help.