As far as I can remember, we see a total of three Joes in the movie. Joe A kills himself, then 30 years later gets sent back and is killed by Joe B, a closed loop.
Joe B, however, changes from the original timeline of Joe A, and manages to escape his captors and sends himself back and is not killed by Joe C.
What changed in Joe B's timeline that caused the break in the timeline? His wife being shot? Something else?