I have my mobile number registered in Aadhaar but I want to replace it with my second number. Can I update it online?
No, you cannot update your mobile number online.Mobile number update in Aadhaar requires Biometric Authentication, it cannot be done online. Please visit your nearest Aadhaar Kendra (Locate one from: https://uidai.gov.in/ ) for this. No documents required for Aadhar update.
It will cost you INR 50 for mobile number update.