Gst cancellation

Sir I am Mukesh Giri opted a gst registration and filed 3 month with nil return because my turnover is less than 20 lacks and also I suffered loss in business but after one month my ca was not traceable he has my I'd and password. After 8 months I received notice from gst that you have to pay tax and interest. So what I can do to cancel it by paying tax or not pls suggest me how to cancel that