The Catholic Church prudently provides for 3 states when making judgements on apparitions.
1) True: nothing that conflicts with the teaching of the church;
perhaps a prophecy fulfilled or an apparition that seems supernatura. lFatima, Lourdes, Zeitun, etc.
2) Nothing Supernatural: this category is reserved for apparitions /messages that dont conflict with the teachings of the Church, but may be ongoing and could go sour. May also be used for apparitions with prophecies which have not come to fruition or even apparitions with messages that meander and over time dont make much sense or impact.. An apparition which has been declared 'Nothing Supernatural' could become true and be moved to the 'True' category. Garabandal would be an example
3) Condemned: apparitions with messages that are contrary to Church teachings. Examples Veronica Luuken Bayside Prophecy--messages against the teaching of the Church, proclaimed miracles.
In all of these matters it is understood that Angels can and do assist apparitions. However, the Devil(s) are fallen Angels and can give false apparitions and messages. The trick is discerning the difference.