How will the defective parts be sent to the mother warehouse/repairing centre for repair by the downstream repairing centres? What is the tax liability

1. The defective parts shall be sent for repair on a delivery challan accompanied by such e-way bill as may be prescribed.
2. GST shall be chargeable on the repair amount, including the cost of parts, charged by the repairing centre.

( FAQ 22: IT/ITES)