Return not filed

My client obtained GST as paint retailer on Oct 2017, however he did not use the said GST number for his business or any other activity and never file any GST return. Recently he started using the said GST and provide the said GST no to paint distributer and purchased the paint since September 2018..... Now he wants to take benifit of recent wavier of GST penalty.....What is the way ahead for the same...very few purchase are shown in the said portal and nil sale entry in the said GST number.....please guide....