Nested comments

Hello,
I have some issue with nested comments.
Each time i do reply, a new comment is created in place of replying to the selected comment.
If I disable the comments in jetpack (jetpack->discussion->let visitor.. to off) then the reply box from my theme (Kadence) is visible and I’m able to correctly create nested
comments.

Do you have any idea about the root cause?
and how to solve it.

Thank you

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