I’ll help you get to the bottom of this issue, @bradmef.
If you’ve added multiple credit cards with the same bank in your QuickBooks Online, it’s possible you’ll encounter this error message.
Before connecting to Online Banking, identify how your bank sends your downloaded transactions. If they download transactions to only one, you connect the parent account. If it downloads to each of the individual accounts, you would attach all of the sub-accounts.
Follow the steps below to connect your credit card:
1. Click the Gear icon and select Chart of Accounts.
2. Locate the bank account to connect.
3. From the Action column, click View Register.
4. Select Connect bank.
5. Follow the prompts to connect your bank account.
Thanks for joining this thread and for trying out the steps that I've provided.
If you encounter the same error and followed the instruction above, I'd suggest reaching out to our Customer Care Team. They have the tools such as screen-sharing that can help double check what's causing the issue.