Is Limbo's 2 and 4 broken?

[(NSW)jhj82]

I tried to do the defense riven (defend an objective while it not take damage). I went to Hydron as usual and popped my 2 and 4 but this time the objective was getting damaged....I've done this riven challenege a lot with Limbo in the past so did something changed/broke? Clarification would be cool. 

[(NSW)RATHURUE]

Don't do Hydron for no-damage defense mission. Try defense on Eris.

The problem with Hydron defense is that enemies use mainly projectile weapons, and Limbo's stasis freezes those projectile when they're flying mid-air. If there's any enemy firing their weapon inside the bubble when the stasis ended, the projectile would go straight to the defense objective, failing the challenge. Compared to that, Kala-azar on Eris has hardly any projectile-based enemies before wave 6 (only few Mutualist Ospreys and Mutualis MOAs will appear near the end of wave 5). The only enemies you need to watch out are those Volatile Runners, which can damage the defense objective should be taken out with non-melee weapons too close to the objective. Try bringing Ignis Wraith as primary and Kuva Nukor or Atomos as secondary, because they can clear enemies straggling on the edge of Catacylsm easily.