So you have you Jekyll post properly appearing in your dev environment but not there when you deploy in production. Here is a few things that are most likely the reason why:

Timezones

Your local dev environment timezone may differ from the remote server.
Make sure you have configured the timezone setting in your _config.yml:

timezone: America/New_York

• Jekyll configration settings documentation
• List of available timezones

Unpublished

Your post may be unpublished by some of your blog’s configuration.
Try to set: published: true in the YAML Front Matter of your post and see if the post show up after re-deploy.
https://jekyllrb.com/docs/front-matter/

Draft

Lastly you post may simply be in the _drafts directory preventing it to be correctly generated in the production build. If it’s the case try to move the post to the correct collection (default: _posts).