Middle name mismatch of deceased person

The name change affidavit should be given by a living person and not by a dead personn neither by the relative of a dead person.

How did this error occur.

If this is an error due to PAN or AADHAR card details, you  can attach  the previous original documents having the correct/actual name and the documents pertaining to the changed name and can give an indemnity bond indemnifying the loss in this  regard if any may arise  future.

You can comply with the requirements in this regard as instructed by the concerned department/authorities  wherever you may find an objection raised in this regard.

If nothing works out then you have no option than to approach civil court with a suit for declaration to declare that your father's name mentioned in different documents differently pertains to one and the same person and can attach the court decree copy to all your claims accordingly