Dear Gopal ji, the link given above will not help you.
If there is a minor mismatch of spelling in the name or a mismatch in the date of birth, then one can rectify the same by uploading a joint declaration. But in your case, there is a major mismatch in the name.
Proof of Identity for Name Change
The person has to prove that both names, i.e., the actual name that matches with the Aadhar document and other documents, and the name registered with PF, i.e., the pet name, belong to the same person and one person only. He has to get it certified from the court on affidavit. The PF department will effect the change on such a document only.
Verification Practices
How did you accept the name, i.e., the pet name of the employee? That means you are not obtaining Form 11 from the employee at joining. You are not verifying the identity of the candidate on his joining. You are practicing Lallu HR Practice, isn't it so?