When something is reportedly true, it means people say it's true, but it hasn't necessarily been confirmed. If your favorite band is reportedly coming to town, it may just be an unfounded rumor.
The word reportedly implies that information has been shared by others, but it hasn't been officially verified. For example, if someone says they've heard that a new movie is in the works, but there's no official announcement yet, then it is reportedly happening. Using the word reportedly helps indicate that the details are not certain, reminding us to take such news with a grain of caution until all the facts are in.