When human death occurs, the released soul atman again manifests a new body based on residual balance of karma at the time of death. Only if matching parents are not available on mother earth the soul atman hibernates in heaven or hell.
Death of human form is not the end of life. The consciousness, spirit existing in our heart we called Prana, soul atman is the real master and controller of human body. It is this spiritual traveler that manifest human form to work out its karma, remove dross impurities within.
Human form is but a medium for soul atman, consciousness within to purify itself. The human body in itself had no cosmic entity. After death of human form, the body disintegrates and dies.
As we are a spirit manifesting human form, after death of body we not only survived but also manifest a new body. This cycle of birth and death continues unabated until human beings reached state of enlightenment and finally moksha salvation.
The state of moksha salvation can never be reached in one lifetime. It is many lifetime before the human form finally reaches state of enlightenment liberating soul atman from bondage of life and death. The cosmic journey of soul atman within ends when human beings gained enlightenment. A pure soul atman in absence of dross impurities within need not manifest a new body.
These facts of cosmic life are well detailed in Bhagavad Gita and Upanishads (independent spiritual treatises).
Governed by ego, if we treat ourselves as a physical body then our life is limited by one single span of life, the present earthly domain.
However if we treat ourselves as a spirit, soul atman manifesting human form then our life comes to an end when human beings gained enlightenment followed by moksha salvation.
In physical form continuity of life does not exist. Human beings never become immortal. Immortality always belonged to the spirit world. In fact a spirit, consciousness existing in our heart was always immortal. Dominated by ego we simply failed to realize our true identity.
Indulging in spirituality when we realized our true identity as a soul atman then our interest in spirituality had no bounds. Thereafter we just wanted to liberate self from cycle of birth and death forever.
Souls’ atmans never want to continue rotating endlessly in the cycle of birth and death. But there was no alternative as souls atmans could not purify themselves and need a medium to work out their karma, remove dross impurities within.
In physical form human beings could never gain immortality. The concept of immortality itself is flawed. That something which cannot birth or die is immortal from the beginning of life. Human form had nothing to do with immortality.