An example of this would be someone saying they're not a fan of the movie musical Wicked, and those who love the film may respond by saying, "NTM on Wicked, it was one of the biggest films of 2024".
For example, someone might text you, "What's up?" and you might reply with, "NTM," meaning you're not doing anything special at the moment. Another possible meaning is "Not to Mention," which is ...