Zalmarath the Colossus becomes invulnerable after dropping to 90% HP – Paris Server, EU

We’re encountering a problem with the boss Zalmarath the Colossus on the Paris server (Standard League, co-op mode). After reducing its HP by 10%, the boss becomes completely invulnerable and stops taking any damage.

We tried attacking it for over 5 minutes, targeting different parts of its body (arm,body, general animation, etc.), but its HP bar didn’t decrease by even 1% beyond that point.

This blocks our progression and makes it impossible to proceed.

Additional Information:
Server: Paris, EU
League: Standard
Mode: Co-op
Steps to Reproduce:
Face Zalmarath on the Paris server.
Reduce its HP to 90%.
Attempt to deal further damage.

Expected vs Actual Behavior:
Expected: The boss should take damage progressively until defeated.
Actual: It becomes invulnerable after reaching 90% HP.

We’d greatly appreciate your help in resolving this issue, as it’s currently blocking our progress. Thank you in advance!

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