If I'm missing a bank transaction like an opening deposit, how to fix it?

I appreciate you posting here in the Community Space, dagdashearth. Let me share some insights and steps to ensure these bank transactions are showing up in your QuickBooks Online (QBO) account.

When syncing your checking account to QBO, QuickBooks automatically downloads the transactions to their most recent updates. If your latest transactions are not showing in your banking tab, I've got some troubleshooting steps to help you resolve this.

Here's how: 

1. In your QBO account, go to the Bookkeeping tab and click Transactions.
2. Select Bank transactions and tap Update.

If these missing transactions are not updated, you can manually download them into QBO. 

Additionally, to ensure these missing transactions are reviewed accordingly, let's verify and check the tile for the bank or credit card account you've downloaded the transaction. To do that:

1. Go to the Bookkeeping tab and select Transactions.
2. Tap Bank transactions and select Link account.
3. Let's confirm if your bank's URL is listed. Enter the name of the bank and copy the URL.
4. Sign in to your financial institution's website using the copied URL.

On the other hand, you can visit this article to learn more about the detailed steps above and know its fixes when encountering any bank errors: What to do if you get a bank error or can't download transactions in QuickBooks Online.

Moreover, you can categorize and match these transactions once everything's on track. Doing so will help you review and modify them to the correct accounts.

Keep us posted in the comments below if you have additional questions about bank transactions in QBO. We're looking forward to any of your concerns. Have a good one!