How can members delete their own topic?

A user in our forum published a topic, and it seems he is not able to delete the topic afterwards. What settings is related to this problem?

It is similar to this question in this forum, but there is no answer in it:

Users can delete their own topics if no reply was posted yet.


Otherwise they should flag the first post for moderator attention and indicate they need it deleted. Remember that deleting a topic with other people’s replies would indirectly remove their content as well.