Hi debbie119,
Thanks for your question and welcome to the community!
To answer your question, yes you can still change data within the GST Liabilities payable section once reconciled but this will most likely throw off your reconciliation and cause a discrepancy.
These types of enquiries can be a bit tricky so I would definitely recommend getting in touch with our support agents who have the right tools to troubleshoot this with you.
You can get in touch by using this link - https://help.quickbooks.intuit.com/en_AU/contact
Kristian.
