Assalamu alaikum, I had a fight with my father, left the house and moved to different location, then my father also moved to a different location. I want to patch up with him but he does not want to keep any relation with me. It has been many years now, I do not know his address and he is not receiving my phone calls, so there is no way left for me to contact him. So, if anyone of us dies in this state, the sin of Qata Ta'alluqi is on me or him?
Qata Ta'alluqi is an Urdu term that many one here would not be familiar with. I think it means repudiation, or in this case to nullify in relationship with your father. There are many verses in the Quran about maintaining the ties of kinship. For example, see: [al-Nisa’ 4:1] [al-Isra’ 17:26] [al-Ra’d 13:25] [Muhammad 47:22-23]
A man said to the Messenger of Allaah (peace and blessings of Allaah be upon him), “I have relatives with whom I try to keep in touch, but they cut me off. I treat them well, but they abuse me. I am patient and kind towards them, but they insult me.” The Prophet (peace and blessings of Allaah be upon him) said, “If you are as you say, then it is as if you are putting hot dust in their mouths. Allaah will continue to support you as long as you continue to do that.” (Reported by Muslim)
Do your best to continue to reach out to him and ask Allah to soften his heart.