Threaded comments not working

I’ve stumbled into a problem. On the WP dashboard -> Comments page, I can see comments and reply to them, and everything works fine. If I go to the posts page where the comment was, I see my reply threaded properly just below the comment I was replying to.

But if I try to reply to a comment from the webpage itself, it won’t let me thread the comment. It shows up as just another comment below the first one. Same goes from the mobile website. Is there some way I can fix this?

My website is https://YETInvesting.com.

Here’s a properly threaded comment that I did through the WP dashboard: https://yetinvesting.com/selling-our-apartment-building-update/?replytocom=34#respond

Here’s a page where I tried to reply to a comment, but it wouldn’t thread it (see my last response to QD):
https://yetinvesting.com/5-reasons-why-you-should-do-your-own-taxes/