Immortal Player glitch

[livid atlas]

I just played a match were upon jamming the person to the right of me and killing the player to my left, there health bar vanished but they were still able to play at 0 health, when it came to there turn they used a cigarette to come back to 1 health from zero? you also couldn't target them because they were consider by the game dead. i only won the match because they offed themselves haha