Step-1: Login to GST portal (http://www.gst.gov.in/) with your user id and password

Step-2: Click on the registration bar from the SERVICES option given in the tab and select the non-core amendment

Step-3: Click on the authorized signatory tab

Step-4: Add new authorized signatory whose email and mobile number user wants to use & fill the whole page like new registration

Step-5: Go to verification tab and submit the application

Step-6: After submission of application please wait for some time so that application can be process

Step-7: Login again with user id and password

Step-8: Go to the authorized signatory tab – deselect the primary authorized signatory check box

Step-9: Select the newly added authorized signatory as primary authorized signatory

Step-10: Go to the verification tab and submit