I’ll make sure that you’ll get to the right support who can help you unlodge and amend your BAS in QuickBooks Online.
Right now, unlodging the BAS needs the assistance of our QuickBooks Support. I'd suggest getting in touch with them since they have the facility and be able to unlodge it for you.
To help guide you in amending your BAS in QuickBooks Online, see the following articles below:
So that we can better support you with unlodging your BAS, I would suggest contacting our support team for further assistance. Please find their contact detail below: