All of my original setup has disappeared???

Did you have a trial account? When you clicked the Buy button, it would open a new blank QBO account.

https://quickbooks.grsm.io/Australia

Hi TLCCleanServices, 

Thank you for reaching out. 

I would encourage you to get in touch with our support team so we can better assist you. Please find their contact details below:

https://help.quickbooks.intuit.com/en_AU/contact

Thank you and please let us know if you require any additional assistance.