Taxes should be setup in QuickBooks Online prior to integrating Revel and QBO.
Login into QuickBooks and click on Taxes > Sales Tax.
Check, on the right hand side under Related Tasks > Add/Edit Tax Rates and Agencies.
Click New or Edit POS Tax, if that has not been set up.
Setting up taxes in AU QBO is similar.
Please go to QuickBooks Online > GST > and setup GST here.
You can also select New Tax to create a new tax in QBO.
For further assistance please contact QuickBooks Online at:
1(800) 914-2688 DNIS:68225