Genesis 40:3

And he put them in ward in the house of the captain of the
guard
Who is generally thought to be Potiphar, since this was the office he was in, ( Genesis 39:1 ) ; unless he was dead, and there was another put into his room, or there were more than one in the same office: into the prison, the place where Joseph [was] bound;
that is, where he had been bound, and where he was still a prisoner, though not fettered and in that close confinement he had been in.