I appreciate you coming back to this thread, @Anonymous. I’m here to ensure that you’ll be able to reimport your suppliers correctly.

In QuickBooks Online, we’re unable to delete your supplier list if the file is imported incorrectly. If it needs to be re-imported, you’ll need to make them inactive first to avoid duplicate entries. Otherwise, you can edit each of them.

When you make your supplier inactive, any transactions associated with them remain in your company data. This prevents messing up your books.

Here’s how:

1. On the left pane, go to the Expenses menu and select Suppliers.
2. Select the Batch actions or your supplier’s name.
3. Click on arrow drop down.
4. Choose Make inactive, then select Yes

    

You’ll want to read through about importing suppliers from email contacts to QuickBooks Online. This contains the things and process you’ll need to know before you import contacts from Outlook, Excel, or Gmail. 

If you want to merge them, refer to this resource for the step-by-step process: Merge duplicate suppliers in QuickBooks Online.

You can check this article to learn more about uploading your data into the program: Common questions about importing data to QuickBooks Online. This will show and explain how to import data into QuickBooks Online as well as how to format or create the file needed.

If there's anything else you'd like to know about recording transactions, feel free to add a comment below. I'm always here to help you more. Have a nice day ahead.