"Rerun" is the term you are looking for, if you like to see on a context, there is this classic scene on "Back to the future" where they install the tv for the first time, but Marty already saw the show and tell the family that it's a rerun, the family goes like: "what you mean you have seen it, it's brand new". Movies are great practice.

It's a 'repeat' or "it's a rerun"

thank you

Do you mean it has been shown on the television before? If so it is a repeat if being shown again.