Is one of your blog posts stuck at the top of your blog page?
When a blog post is marked as a sticky post, it sticks to the top of your blog page even when there are newer posts. Normally, your most recent post appears at the top of the blog page, so if you unmark your posts as sticky they will be ordered with the most recent post at the top.
The WordPress app currently doesn't have an option to change a post's sticky status, so you can edit the post in a web browser to change that: