Hi juliaah33,
Thanks for posting in the Community!
Once you enable the BAS electronic lodgement, you can't get back to the set up page. If this has been enabled in the past, that means you'll be able to lodge your BAS to the ATO directly from QuickBooks Online.
If the BAS amounts won't match, you can run a Transactions by Tax Code report to check if the GST code assign on the transactions are correct and GST Amendment report. An amendment appears when a transaction from a previously lodged BAS period has been edited after the BAS was lodged, carrying forward the changes to the BAS you’re about to lodge.
For more detailed information, you can check on this article: What to do when BAS amounts look incorrect.
Feel free to drop a comment below if you need further assistance. Have a great day!
