What is the ruling on one who repeatedly returns to a sin after repenting from it, despite the intention to abandon it and being affected by the seduction of Satan and society's encouragement to sin?

Relapsing into sin after repentance does not invalidate the first repentance, provided that it was sincere for Allah and met the conditions of repentance. He should increase his seeking of forgiveness, for in the Hadith (definition): "He who seeks forgiveness is not considered persistent in sin even if he repeats it seventy times a day." Among the things that help one remain steadfast are: reading books that encourage good deeds and warn against evil, praying in congregation, attending religious lessons, associating with good people, and avoiding bad company.