Learn Portuguese (Portugal): Pois, mas a rececionista já chamou a senha dele. - Right, but the receptionist already called his queue ticket.

Used by itself, pois often acts as a spoken marker meaning 'right', 'exactly', or 'I know'. Here, combined with mas (but), the speaker is acknowledging what the other person just said before immediately introducing a problem or counterpoint.

I thought senha meant 'password'. Why is it translated as 'queue ticket'?

In Portuguese, senha is used for a digital password, but it is also the word for a physical paper ticket with a number on it that you take to wait your turn (like at a bakery, pharmacy, or clinic). The verb chamou (called) gives away that this is a waiting room scenario.

Could I say a sua senha instead of a senha dele?

Grammatically, yes. However, sua can mean 'your', 'his', 'hers', or 'theirs'. Because of this ambiguity, Portuguese speakers usually prefer dele (his) or dela (her) placed right after the noun. It makes it instantly clear that the ticket belongs to a third person ('him'), not to the person you are talking to!

Does the word rececionista change if the receptionist is a man?

The noun itself doesn't change because professions ending in -ista are gender-neutral. You only change the article before it. So, a female receptionist is a rececionista, and a male receptionist would be o rececionista.