Glad to have you here in the Community, @a-abrams
The error 9999 is a reported script error that interrupts the connection between your bank and the program. But before jumping into troubleshooting, may I know the name of the bank you use? Your bank may be undergoing system maintenance. You may visit your online banking website to see if there is a notification that requires your attention.
Moreover, let me provide some information about the error message and help ensure you can connect your bank account.
Check your bank or credit card's website.
If downloads seem slow or stuck, the issue may be on the bank’s end. Sign in to your bank’s website to check. First, get the URL QuickBooks uses to connect:
- Go to Transactions, then select Bank transactions.
- Select Link account. Note: You won’t add an account, you just need the listed URL.
- Search for your bank and select it.
- Copy the URL listed for your bank.
- Sign in to your bank or credit card's website using the copied URL.
If you can sign in, it's a good sign that there isn't a major issue. Next, check the following:
- Check your account for messages, notifications, or alerts.
- Look for any display issues as you navigate the website. These can block QuickBooks from downloading new transactions.
- Check your bank’s website for any announcements about new security requirements.
If everything looks good, go back to QuickBooks:
- Go to Transactions, then Bank transactions.
- Select Update.
Update your bank info in QuickBooks.
Did you recently update anything on your bank’s website, like your account number, username, or password? If so, update that info in QuickBooks as well:
- Go to Transactions, then Bank transactions.
- Select the tile for the bank account. Then select the Edit ✎ icon.
- Select Edit sign-in info.
- Update your info as needed.
I've also included an article that can help organize your transactions in QBO: Categorize and match online bank transactions in QBO.
Fill me in if you need more guidance about banking matters in QuickBooks Online. I'm always ready to back you up. Take the best care!