Let me get the help you need to ensure that you would be able to import .CSV file into your account.
To help us resolve the problem, let’s double check the format of your file if it is one of the accepted formats when importing transactions in QuickBooks Online and make sure that your file doesn’t break the following formatting restrictions:
Special characters are not allowed.
Zeros (0) are not allowed anywhere in the file.
Correct any transactions that display an amount in the Description column.
Remove the word amount if it appears in the name of the Credit or Debit column.
MAC users must save the file as a Windows CSV file.
Correct and standardize the Date format to a single format (for example, dd/mm/yyyy).
Some banks provide the day of the week and include it in the Date column (for example, 20/11/2018 TUE in column A) which is not an acceptable format. To correct this, split the date and the day of the week in two separate columns.
Once the format is verified, kindly try to import transactions again. However, if the error still persists upon importing, I suggest contacting our Customer Care Support for them to check your account. They have the necessary tools like screen sharing to check and pull up your account in a secure environment.
As always, you can reach back out if you have further questions about importing transactions in QuickBooks Online. I’d be happy to answer it for you.