When setting the thread level to any number above 1, say 2, comments are only nested 2 levels as expected - unless I hit the quote button.

If someone clicks on the quote button, the reply button appears for as many levels as someone continues to hit the quote button. That means that the nested threads go beyond 2, 3, or however many. When the quote button is clicked, the quotation section doesn't appear, instead the reply button appears.

What am I doing wrong or what is going wrong and how can I stop it?