Hello there, Saddle. Is the customer profile set to a specific GST rate or based on location? Also, is the service item set to taxable in the Products & Services section?
The reason your GST is being wiped out may be that the service item is set to non-taxable, or there's no default tax code assigned to that customer. To verify this, simply navigate to your Service item>Edit and check its tax status. Then, go to Customer Profile > Edit to ensure a default tax code has been assigned.
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