Yes, there is. 

I have all the information to import those missing transactions into QuickBooks Online.

You can bring those missing data by downloading them in a CSV file format and then performing a manual upload to ensure they appear in your bank register. I can walk you through the step-by-step guide.

1. Log in to your bank or credit card's website.
2. Follow the instructions provided by your bank to download CSV files containing your transaction history to your computer. Every financial institution has different steps. Here are steps for Bank of America, Chase, and Wells Fargo.
3. Make sure the date range for the download is at least one day before your oldest transaction.
4. Download the transactions and save the file in a location that is easily accessible, such as your computer's desktop.

Then, upload the transactions to QBO:

1. Navigate to the Transactions tab and click on Bank transactions. 
2. Locate and click on the blue tile representing the account where you want to upload the transactions.
3. Click the Link account ▼ dropdown and then Upload from file.
4. Choose either the Drag and drop option or select files to locate and select the file you downloaded from your bank. Then, click on Continue.
5. In the QuickBooks account ▼ dropdown, select the account you want to upload the transactions into. Then select Continue.
6. Follow the onscreen instructions to match the columns from the file with the appropriate fields in QuickBooks. Then, click on Continue.
7. Select the transactions you want to import, and click on Continue.
8. Confirm by selecting Yes, then click on Done to complete the process.

After obtaining your banking data, take the necessary step of categorizing the transactions accurately to maintain proper accounting practices.

Additionally, it is crucial to reconcile the account to ensure the integrity of your financial records.

Let me know if you have further questions about handling missing transactions and other related issues. I'll be here to assist.