It is, but only during the flashback scenes in TLJ showing what happened between him and Kylo.
Exactly - the only time he’s using the saber that’s supposed to be green, it is green, therefore there’s no problem.
https://www.youtube.com/watch?feature=youtu.be&v=QwWrmSP65lM
I assume you didn’t pay attention to the hilt. This is the original scene:
https://www.youtube.com/watch?v=YdgxfH_nPIY&t=95
It’s clearly Anakin’s saber.