"You were once a human hero, a Watchman willing to fight for humanity." Every Watchman who reincarnates as an angel has a record of their identity. Following the previous agreement, an angel comes immediately, returning his previously left weapons, equipment, and personal belongings according to the record, as well as his life data.
This can make angels understand their origins, but it can't restore their previous memories, because these are all unfamiliar to them. They are like reading someone else's story, viewing everything about their past life.
"So, my past life was a human hero!" The Six Wings Angel who had just reviewed his past life profile showed surprise then calmness in his eyes. There was no more confusion, he understood his origin, "Since I am a hero, then I will keep my current name, still Angus."