Step 1: login to GST Portal (www.gst.gov.in ) using the login credentials.
Step 2: Go to Services-Registration-Amendment of Registration Non-Core Fields.
Step 3: Select the Authorised Signatory Tab.
Step 4: Select the edit option shown in the Authorised Signatory Person, de-select the Primary Authorised Signatory checkbox and save it.
Step 5: After saving the Detail, click on add new tab and create a dummy authorised signatory by filling the required details.
Step 6: During filling the Details, make sure that Primary Authorised Signatory checkbox is selected, new E-Mail Id and Mobile Number is filled.
Step 7: Click on edit option of dummy authorized signatory and save it.
Step 8: While saving the details, it will ask for the OTP verification which will come on the new e-mail id and mobile number.
Step 9: Click one more time on edit option of dummy signatory and uncheck the primary authorised signatory and change the e-mail id and mobile number and save it. After saving the details, delete the dummy signatory.
Step 10: Click on edit option of Proprietor and select the checkbox of Primary Authorised Signatory and save it.
Step 11: Updated e-mail id and mobile number will be saved in communication details.
Step 12: Click on the verification tab and submit the application with DSC/EVC.
Step 13: It will generate the acknowledgment after 15 minutes, but we can check the status in My Saved Applications.
Step 14: After Successful Validation, the profile will be updated with new E-Mail Id and Mobile Number.