Comment box not appearing

I am using ‘StoreFront’ theme with a child theme in my website.

I need comment box to appear under each posts in my site. Instead of a comment box what appears is a link ‘Leave a comment’ which when pressed takes me nowhere.

I have tried all what is suggested in the forum replies as below;
Under “Settings”, ‘Discussion’ tab,
? Allow people to post comments on new articles .. unticked,
? Comment author must fill out name and email .. unticked.
? Users must be registered and logged in to comment .. unticked.
? Anyone posts a comment .. ticked.
? A comment is held for moderation .. unticked.
? Comment must be manually approved .. unticked.
? Comment author must have a previously approved comment .. unticked.

In Screen Options, Comment box was ticked.
All the Comments were edited to ‘Allow’ comments.
All plugins were de-activated and still the Comment boxes not appear in pages, nor under posts.

Whatever I did so far, only this ‘Leave a comment’ link appears under each post which does nothing.

Please help me to rectify this problem.