It is not forbidden by the Church but it is discouraged
[CONGREGATION FOR DIVINE WORSHIP
AND THE DISCIPLINE OF THE SACRAMENTS
DIRECTORY
ON POPULAR PIETY AND THE LITURGY
PRINCIPLES AND GUIDELINES](
http://www.vatican.va/roman_curia/c...on_ccdds_doc_20020513_vers-direttorio_en.html)
Vatican City
December 2001
217 when the daily events of life, which have nothing or little to do with our progressive maturing on the journey towards Christ are read schematically or simplistically, indeed childishly, so as to ascribe all setbacks to the Devil and all success to the Guardian Angels. The practice of assigning names to the Holy Angels should be discouraged, except in the cases of Gabriel, Raphael and Michael whose names are contained in Holy Scripture.
Well from my understanding that is for veneration of angels found in the Book of Enoch (other than Gabriel, Raphael, and Michael) namely Ariel/Uriel, Jophiel, Chamuel and Zadkiel. One can safely assume the angel names coming from New Age sources should be discouraged too. They should not be invoked in prayer. And parents shouldn’t be using them for baby names. I guess this perhaps applies to space alien too,
e.g. Raël.
When a person names their guardian angel they are aware the name is only a proxy for the angel’s real name. In the back of their mind they are still thinking of their guardian angel, and asking their guardian angel for intercession. However this is not the case for angel names not found in sacred scripture. When they invoke a non-canonical angel’s name
e.g. Ariel they believe that is the angels name, not a proxy. They’re also relying on the intercession of an angel the Church does not recognize to exist.
What the Church frowns on is thinking of your guardian angel as the source of good luck, like “my guardian angel helps me pick out winning lottery numbers.”
“Deviation [in the veneration of angels] also takes place if the everyday events of life come to be seen in a schematic and simplistic mode,” states the directory, "whereby the smallest setbacks are attributed to malign forces and successes and achievements which have nothing to do with man’s path towards the maturity of Christ are attributed to one’s guardian angel."