Sometimes when I killed the illager captain I did not recieve bad omen

Do you have armor with thorns enchantment? If so then may be a duplicate of MCPE-55282.

No I cannot use the enchantments of thorns,but sometimes in my one word I did not recieved a bad omen effect when I killed the illager captains.

How are you killing the illager captain, then?

Using diamond sword

I can confirm(I killed the captain of a patrol. I got the achievement, but not the bad omen effect), but and I am playing Java edition snapshot 20w28a for 1.16.2. Is there an issue for my edition and version?

@Arceussinnoh did you have fire aspect on your sword?

No

To clarify, do you never get bad omen from killing any patrol captain, or does this only happen sometimes?

Only happen sometimes

Thank you for your report!
However, this issue has been closed as Cannot Reproduce.

We were unable to reproduce the problem you are describing in the latest version.

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