You are not registered in GST for the period of July, 2017 so you cannot raise the Invoice under GST.
Option 1: Revise the bill without GST and give to your client and set off the amount
Option 2: Revise the bill and it shall be dated after 11.08.2017 with GST and ask the client to take the credit in the month of AUGUST.
chatCommentsthanks sir. - SUMER SINGH RATHORE