Olivia Culpo and Danny Amendola may have forgotten old acquaintances -- at least one of them -- because it looks like they're back together.
Danny and Olivia each posted identical videos of fireworks to their IG stories ... videos obviously shot on New Year's Eve.
The videos were shot at a beach location, and the fact he plays for the Dolphins may be a geographical clue.
Olivia and Danny broke up a few months ago after he hit the beach with a super hot woman.