It's good to see you here in the Community, @RFS PFA.
Let's get your January transactions to show up so you can proceed with reconciliation.
If this is the first time connecting your bank account to QuickBooks Online (QBO), it's the reason why your January transactions aren't showing. Please know that QuickBooks only downloads bank transactions past 90 days. In this case, you'll want to manually upload transactions into QuickBooks Online.
However, if you're referring to your transactions that aren't showing on your bank register, you'll need to add them first from the Banking page. Here's how:
Sign in to your QBO account.
Click Banking from the left menu.
Select the appropriate bank account.
Go to the For review tab and add your downloaded transactions.
Once your January transactions are already added, you can now proceed with reconciling accounts in QBO. This is to ensure your QuickBooks transactions match your bank statement.
Should you need any additional assistance while managing your bank transactions, you can leave a comment below. I'll be sure to get back to you, @RFS PFA.