After using 10 terror essences this week, my Codex activity shows 10/10 terror essences consumed but does not provide the reward (either in battle points or equipment). My last terror essence used was a joint bounty with 1 other player.
In addition to a description of the bug you are reporting, please provide:
The legendary item is awarded when you claim the completed Battle Pass task. If you have consumed 10/10 essences, there should be a Claim button on the task. Is this not what you see? Could you post a screenshot of your Codex?
I’ve had no problems doing this in previous weeks, as the claim button would appear. Here, you can see 10/10 consumed, but no claim button. I’ve restarted the game, but to no effect.