When saving an expense, an airline expense credit, receive the error message "The XG amount cannot exceed the tax amount". The amount that is credited is 348.40CAD and system automatically has 40.08 as HSTON Amount. It asks for "Airfare XG Amount" which on the invoice it shows as 11.69 CAD. But whatever amount I insert the outcome doesn't change and I still receive the same error message. 

Appreciate if someone helps to resolve this issue.

Thanks