Mutuation via Agreement Sale & Name Mismatch

Hi, In 1984, a property was bought in Delhi, by 'unregistered but notarized', "Power of Attorney" & "Agreement to Sale" along with a registered "WILL".  This was the standard procedure of buying property then, especially for not so educated / informed people. In 2002 Municipal Corporation made an assessment for the property tax and mutuation was done on the basis of the "agreement to sale". Today in 2021, should the property still be registered by a "sale deed" through the power of attorney? Or any other Deed?Or else, is the mutuation by MCD is good enough to establish the title of the property in order to transfer the property in future via sale or gift or will. Another part of the question is about the name in the Mutuation record. The Name in mutuation record has been recorded from the "agreement to sale" but over the years that name has changed with surname being added. In 1984 the name on the "Agreement to Sale" was Bhavri Devi. In 2002 MCD recorded the same name adding the surname 'Bavri Devi Saini". At present the name for all practical purpose is Bhavri Saini in her Passport / Aadhar / PAN etc.  Should this be altered at the MCD level on the mutation certficate by providing the Self declared "Affidavit" that all the names are of the same person? Now, in case the sale deed is mandatory to be  registered in favour of Bhavri Saini through "General power of Attorney" what should the document name the 'buying' party as? Bhavri Devi Saini or Bhavri Saini. Please enlighten. Thanks a lot.