I appreciate you for sharing the name of your financial institution. I can share some details about how the Banking feature works in QuickBooks Online (QBO).
When you connect a bank account in QBO, your transactions download automatically. The data that is imported into our system will depend on the information your bank shares with us.
Since there are missing transactions, I recommend checking your bank's website. It may be possible that they aren't showing yet in your account.
If it's already reflected on the website, I suggest refreshing the account. You can use the Update button to refresh the connection with your bank.