GST Query

Jasmine kaur (Student CA IPC / IPCC) (31 Points)

06 June 2018  
I am facing a problem in GST .. Actually there is a person who is still paying service tax for their supply of services . I want to know whether service tax paid by him can be adjusted with GST or is their any provision under GST/STAX under which he can claim the refund of service tax already paid !!
If yes then plz let me know the section under which he can proceed further.