Welcome back to the Community space, nunnerst.
I'll ensure you'll be able to add a personal transaction in QuickBooks Self-Employed.
When adding a transaction, the software uses the Business type by default. However, you'll be able to separate personal and business transactions. I'll show you how.
- Go to the Transactions menu.
- Select those transactions you want to change to Personal.
- Click the Human icon to mark it as personal.

- Once done, hit Apply button.

In addition, you can create a bank rule to speed up your review if you have the same type of transactions. Check out this article for more details: Create rules in QuickBooks Self-Employed.
If you need additional resources for future QBSE tasks, please see the following links below:
We're always available to help you if you have further questions or concerns. Have a great day.