I appreciate your time posting here, userpreneedsteve.

When you say to separate the accounts, are you trying to create a new company to separate the file? If so, you'll want to follow the instructions on how to subscribe to a new company in his article: Create or add another company.

Then, export and data from one company and import the Chart of Accounts, customer and vendor lists, and products and services to the new one.

To export:

1. Go to the Gear > Export data.
2. Select the Reports and List and then click the Export to Excel button.

Once done, open the new company and import the data.

1. Click the Gear > Import data.
2. Select the data you want to import.
3. Click the Browse button and locate the file.
4. Follow the on-screen instructions to map the columns.

For more details and steps you can check out these links:

• Export your reports to Excel from QuickBooks Online
• Move your chart of accounts to QuickBooks Online
• Merge companies, data files or copy lists

On the other hand, if you've merged an account in the Chart of Accounts, you can make the old account active. Then, manually transfer the transactions back to the old account. 

Here's how:

1. Go to Accounting > Chart of Accounts.
2. Click the Gear icon above the Action column, and put a check mark on the Include Inactive box.
3. Find the account and click the Make active link.
4. Open the account where the transactions were transferred and click the Edit button.
5. Change the Deposit to account and select Save and close.

You can find more details about merging an account in this article: How to merge accounts, customers, and vendors.

If you're referring to something else, please let me know in the comments. I'll be around to help you some more.