i excluded previously uploaded banking transactions and now when I tried to upload the banking transactions, quickbooks can't seem to upload the transactions anymore

The reason your QuickBooks isn't allowing you to re-upload bank transactions is that it remembers even the excluded transactions to prevent mistakes or duplicates, Gctai2000.

To assist you properly, did you receive any error messages or notifications from QuickBooks when you attempted to re-upload the transactions? Any additional info or screenshot would be appreciated. You can also contact your bank to check for any connection issues or restrictions on your bank's end that might be preventing the successful upload of data.

When you connect your bank to QuickBooks and exclude downloaded transactions, it records that action. So, when you try to re-upload those transactions, QuickBooks flags them as duplicates and blocks the upload to maintain data accuracy.

Excluding a transaction doesn't erase it from the system. To prevent QuickBooks from recognizing already uploaded transactions, you can delete the excluded ones for full removal. Alternatively, undoing the exclusion will return the transaction to the For review window, so you won't need to re-upload it later.

Also, ensure that the CSV file you used when uploading your transactions has the acceptable format by QuickBooks.

You can refer to this article for guidelines when you upload transactions into QuickBooks: Manually upload transactions into QuickBooks Online.

If you need help in categorizing your entries to avoid double transactions, refer to this article: Categorize online bank transactions in QuickBooks Online.

Please leave a comment below if you have more questions about this or anything else. The Community team is here to assist you.

@gctai2000 

Try opening your QBO account on any private/incognito browser.