It depends on the relevant pension rules applicable to the organisation concerned. Every government / organisation may have its own separate pension rules. You have to check the relevant rules applicable to the organisation concerned, i.e., electricity board in Bihar where you father was working.
For example, for the central government employees, in the case of an unmarried son, family pension may be payable (if eligible) until he attains the age of 25 years or until he gets married or until he starts earning his livelihood, whichever is the earliest.
You have to check your rules.
Moreover, it is not clear from your question whether the service of your father was pensionable. Is he considered as retired? Has he been considered as dead, since family pension is payable only if the employee himself is dead? You said that your father is untraceable since 1996. So, what happened after that? Sometimes, in such cases, the employee concerned is removed / dismissed from service on the ground that he is absent from duties, in which case pension may not be payable depending on the rules of the organisation.
For 22 years, it appears that you have not taken any action. Consult some local expert with full facts and relevant rules.
Dr. Ashok Dhamija is a New Delhi based Supreme Court Advocate and author of law books. Read more about him by clicking here. List of his Forum Replies. List of his other articles. List of his Quora Answers. List of his YouTube Videos.