I can help import your bank transactions, @darlingaslan-out.
You'll have to make sure that your CSV file is formatted correctly so you can import your account successfully without any error. These are some formatting samples that you'll have to avoid:
• Standardize the date format to a single format (for example, dd/mm/yyyy).
• Remove the word amount if it appears in the Amount column.
• Remove zeroes (0) from the file and leave those cells blank.
• Correct any transactions that display numbers or special characters in the Description column.
• Mac users must save the file as a Windows CSV file.
After changing the format, you can continue importing the file. Check out the article for the steps: Manually import transactions into QuickBooks Self-Employed.
Additionally, here's an article that you can read to help manage your downloaded bank transactions in QuickBooks Self-Employed:
• Categorize transactions
• Split transactions
Reach out to me directly if you have additional questions about working in QBO. I'm always ready to lend a helping hand.