Canada's National Advisory Committee on Immunization's revised guidelines, the new guidance calls for the Pfizer-BioNTech offering due to "Lower reported cases of myocarditis/pericarditis ... compared to Moderna Spikevax."
What myocarditis/pericarditis? This is a conspiracy theory. The vaccines are safe, bigots. Take your poison and shut up.
Got any links to government announcements that it's "banned"?
Everything I've read - and I can't read all of it - says that some countries are limiting its use in young people only, but it's usually because they have an adequate supply of another vaccine. I doubt you'll find anywhere that has "banned" its use if there's nothing else available for young people.