Question: who to activate uan number?
Answer: Go to the EPFO website and click Activate UAN on the bottom-right corner of the page.
Key in your UAN, name, date of birth, mobile number, and the captcha text. ... 
You will now get a one-time password (OTP) on your mobile number. ... 
Verify all the details on the EPFO page, and tick the check-box next to I Agree.