Happier was released on May 21, 2021.
Fans are speculating that the Sour album is about Joshua Bassett (Olivia's ex-boyfriend) and Sabrina Carpenter (Joshua's current girlfriend); which is likely to be true.
Olivia's first song was driver's license which was released on January 8, 2021 (also in Sour).
If the songs are about one thing, how did she say "We broke up a month ago" in Happier while she has sung about her ex in January too?