Staying on top of the account is very important in QuickBooks Online, @bargie231. I'm here to help you recover the missing transactions.

We'll have to first go through your account history to ensure everything is recorded completely. Here's how:

1. Open the Bookkeeping menu and choose Chart of accounts.
2. Find the bank account and hit View register.
3. Locate the checks and deposits that you manually added. 
4. Click on it to get more information.

That should give you a complete summary of the transactions.

After that, let's check the uncategorized area on your COA. When transactions aren't categorized, QuickBooks usually add them to the Uncategorized Income or Uncategorized Expense account. It's likely that the missing transactions are there.

1. Open the Bookkeeping menu and choose Chart of accounts.
2. Find the Uncategorized Income or Uncategorized Expense account.
3. Click on Run report.
4. Once the report is opened, search for the missing transactions.

If you ever see the data you want, you can unmatch the transactions and move them to the right account. If not, I recommend you import the transactions manually into QBO.

Once everything is back to normal, kindly read this module to find out how to match your monthly account balances in QuickBooks: Reconcile an account in QuickBooks Online.