In the R season of the classic anime of Sailor Moon, Chibi-usa had a flashback memory of her surprise birthday party in the 30th century Crystal Tokyo, in which Sailor Mercury, Sailor Mars, Sailor Jupiter, and Sailor Venus were present (Wiseman made use of the piece of memory of the span of time during which the secret about the surprise was being kept from her in order to turn Chibi-usa into Black Lady). Chibi-usa also had a faint memory of the same four sailor soldiers fleeing with her while Crystal Tokyo was being attacked, but in this memory, the four people are darkened silhouettes. I can understand that, due to the trauma of the attack and worry about her mom, Chibi-usa might not remember clearly who helped her escape. After these events, she time-traveled to the 20th century where she met Sailors Moon, Mercury, Mars, Jupiter, and Venus in their solider forms (as well as met them in their civilian forms).
If Chibi-usa had the clear memory of the birthday party, why didn't she immediately recognize those same four sailor soldiers when she "re-met" them in the 20th century? Didn't the party scene indicate that they were her friends and she knew their names?
Is this a plot hole?
(The manga does not feature the birthday party memory, so I am looking for answers regarding an in-universe explanation for the classic anime canon.)