On the island of Ogygia where she lived. She did not need a prison as Odysseus had no ship to get away on.
Odysseus stays with Calypso [The Hider] on Ogygia for seven years.
Calypso, if memory serves.
7 years
keeping Odysseus prisoner on her island and preventing him from reaching home
After keeping Odysseus as a prisoner of love for seven years Calypso has to obey Zeus's commmand to set O. free. She also shows him where to get material for him to build a boat.
Seven (7) Years
i believe it was the goddess calypso
Be more specific with your question, please. However, I believe you are referring to Calypso. She kept him on her isle for seven years.
Odysseus met Calypso on her lush island of Ogygia.
Calypso offers immortality to Odysseus
Hermes tells Calypso to let Odysseus go.
Calypso