Hi there, smarque.

I'll share information about how to successfully import your transactions using CSV files without any errors and issues.

The issue you're experiencing occurs if the bank file format isn’t compatible with QuickBooks. Some financial institutions have set them for the file to be uploaded without flaws. That said, I suggest reviewing your CSV file and enter the format based on the requirements.

• 0's are not allowed anywhere in the file, e.g $0 should be left blank
• $ symbols are not allowed, e.g $234 should be 234
• Commas for thousands are not allowed, e.g 2,111 should be 2111
• Other special characters such as #, %, and & are not allowed.
• Correct any transactions with the amount showing in the description column
• Remove the word “amount" if it appears in the credit or debit column, i.e. credit amount, debit amount 
• Correct and standardize the date format to a single format i.e. dd/mm/yyyy
• MAC users must save the file as a Windows CSV file

For additional information, you can refer to this article: Import bank transactions using Excel CSV files.

You can check this article to see a few things to check before importing again your transactions after getting an error: Common errors for importing bank transactions using CSV.

Once done, you can now your bank and credit card transactions after you download them into QuickBooks to avoid duplicate entries. Please refer to this article to see the detailed steps: Categorise and match online bank transactions in QuickBooks Online.

Please know that you're always welcome to post if you have any other concerns. Wishing you and your business continued success.