Jega-Jones
Level 1

Changing GST on expenses

How do I change the GST amount on taxi receipts? 

For example - the charges are:

 

Sale $88.29

Service Fee $4.82

GST $0.48

Total $93.59

 

The system calculates the GST on the total rather than just on the service fee. 
How do I adjust the GST - do I need to do two transactions?