The story "Sneaking Around part 1" has the following dialogue:
Márcia: O que você está fazendo?
Pâmela: Indo pro escritório do meu chefe.
Márcia: Ah, desculpa. Então, liga para mim depois.
But I thought that "desculpa" and "liga" are the congugations for "tu", but Márcia addresses Pâmela as "você", so why doesn't she use the conjugations for "você" which are supposed to be "desculpe" and "ligue"?
Later we also have:
Márcia: Sai daí!
Pâmela: Se eu sair, eles vão me ver!
Márcia: Faça alguma coisa!
Again, "sai" is for "tu" (for "você" it's "saia") but "faça" is for "você" (for "tu" it's "faz").
It looks like they just switch freely between "tu" and "você". What's going on here?