In June 1981, the Blessed Mother reportedly began appearing regularly to several children in the town of Medjugorje, which is located in the Diocese of Mostar-Duvno, then part of Yugoslavia. (The diocese is now part of the nation of Bosnia and Herzegovina.)
In 1985, Mostar-Duvno’s bishop Pavao Zanic determined that the apparitions were not authentic, i.e., not of supernatural origin.
In 1991, the bishops’ conference of Yugoslavia ruled that the supernatural character of the reported apparitions could not be affirmed. This is different than a definitive declaration that there is no supernatural character.
Bishop Zanic maintained his position until his retirement in July 1993, when Bishop Ratko Peric succeeded him. Throughout his tenure in Mostar, which lasted until July 2020, Bishop Peric consistently reaffirmed the decision of his predecessor.
Bishop Petar Palic is the current Bishop of Mostar-Duvno, and he has not overturned his predecessors’ decisions.
The Holy See, consistent with the rulings of the local bishops, has allowed pilgrimages to Medjugorje, provided they don’t present the reported apparitions as approved by the Church, and has forbidden the faithful from participating in events where the reported seers present their reported apparitions as of supernatural origin (see this for more information).
Those who have experienced conversions—or a deepening of faith—associated with pilgrimage(s) to Medjugorje should know that the validity of their experiences does not hinge upon whether the reported apparitions are declared of supernatural origin. Indeed, the sacraments are valid at Medjugorje, and the Blessed Mother can—and does—fruitfully intercede for those who seek her sincerely, wherever that may be.