All dedicated Satanists, at the moment we die, our gods are immediately aware of it and are immediately there to protect us and guide us, and take our soul to their home in Duat. In Duat, our life in the next generation is planned in some amount, the astrology around Earth is closely observed. There may be more or less planning depending on the person, for some NPC mindless person it probably doesn't matter as much. And when the time is correct that the Astrology around Earth is correct so that the Natal chart is the most similar to our soul, we are reincarnated back to Earth in that moment. This is for continuity, so that our soul remains relatively similar between the different generations. There may be some differences in your life, but big things like personality would generally be extremely similar. If it is planned for somebody to have a certain job in this world, or to accomplish something specific and important, then they may be reincarnated at a time which would provide an Astrological influence to help this job be accomplished.
The force which reincarnates us, which carries our soul from Duat back to Earth, it is required for the astrology to be at least similar to the forces of our own soul, to act like a magnetic force which helps draw our soul back to earth. If the astrology is the exact opposite from who you are and the energies within your soul, it would repel you, it just would not fit.
Most people, even who are not Satanists, are all reincarnated in this way. It is extremely rare by comparison for a person to be a ghost and to stay here. One example is during war, if there are many people who die in horrible ways in the same place at the same time, it is possible for the soul to be damaged, to become lost on some other level, or to be partially dissipated and no longer be a complete soul. Possible, but extremely rare. In that case, the majority of the soldiers would be taken by the gods and be reincarnated, but it is possible that some are lost. This is not anything for you or anyone else to worry about. All Satanists are the top priorities for the gods, and our souls are all highly protected and safe, and at the moment we are dying there are gods immediately sent to us to help us and protect us.