All my transactions for 2020 March through October are missing. They were there last month. This my first time using this software!

Hello there, @userrockgardenengrav.

Let me share some information to ensure that your bank transactions are tracked accurately.

It's possible that the transactions were already into your register. You an follow these steps to in locating your downloaded bank transactions:
 

1. Go to the Accounting menu.
2. Choose the Chart of Accounts.
3. Locate the bank.
4. Choose View register at the right under the Action column.
5. Click the Funnel icon above the Date column.
6. Select the transactions' Status and its Type. Then, enter the date afterward.
7. Hit on Apply. 

If the problem continues, I recommend undoing the categorized transaction from the banking page and add them again.

Here's how:

1. Open your QuickBooks Online account, then go to the Banking menu.
2. Select Banking, then look for your account.
3. Click on the Categorized column.
4. Choose the item/transaction, then tap on Undo under Action.

Also, I've added these articles as additional guide in managing your downloaded bank transactions:

• Bank transactions are duplicates, missing or wrong or bank balance not updating.
• Categorize and match online bank transactions in QuickBooks Online
• What to do if you get a bank error or can't download transactions in QuickBooks Online

Get back to us here if you have other questions or concerns. I'm always here to help.