This is the 6th Movie.
Satoshi, Haruka, Takeshi, and Masato come upon the festival of the Wishing Star of Seven Nights. During their enjoyment, the legendary pokemon, Jirachi, decends from the heavens and befriends Masato. Jirachi, with the power to grant any wish, is sought after by many people wanting to claim its power. One man seeks to use its legendary power to revive an ancient pokemon known as Groudon, unaware of the dangers hidden within Jirachi's powers
(Source: Anime News Network)
— Description from AniList community (anilist.co).
