Cleantalk conflicts with comments

Hello,

I’m using Learndash for my courses on my WordPress website. On some of the lesson pages we use comments. Recently we found that unique comment entries are all nested under the first comment in multiple levels. Therefor comments are pushed to the right and become smaller and smaller.

Activating and deactivating the Cleantalk plugin resolves the issue. But of course we would like to have the plugin activated to prevent us from spam.

Can you provide solutions?

Thank you
Karin