Cancellation of gst registration

Hello Every one

Please note I have submitted my New Registration on 03/07/2017 but till 19/07/2017, I haven't received.Only Shown Pending for Order.

Then after I have registered again & I got my new registration with in 2days.

but yesterday 16/08/2017  received another number which I registered before.

kindly help me out how i can cancel this registration.

Thanks.