When starting with an opening balance or creating a new bank journal with an opening balance before the beginning synchronization, here's how to match the opening balance in the bank journal with the amount in your balance:

1. Open your bank journal.
2. If your journal is already synchronized, you will see a list of transactions from your bank.
   
   
3. Go to the oldest transaction and click on "Statement." indicate the Starting balance of your bank account 
   
   
   
4. In the window that opens, enter the starting balance of your bank account in the "Initial Balance" field.
   
5. Click "Save."

See the tutorial