what was the reason behind it?
Because of its supposed references to drugs.
A Day in the Life
The song became controversial for its supposed references to drugs. 
what is the song a day in the life about It strongly informed by Lennon's LSD-inspired revelations, in that the song "concerned 'reality' only to the extent that this had been revealed by LSD to be largely in the eye of the beholder" which band sang this song? Beatles what is lsd mean? UNANSWERABLE what genre of song is this? UNANSWERABLE who are all part of the band you mentioned above? John Lennon, Paul McCartney, George Harrison and Ringo Starr who is the fourth person mentioned? He is an English musician, singer, songwriter and actor, famous as the drummer for the Beatles. who influenced the band? The band's earliest influences include Elvis Presley, Carl Perkins, Little Richard and Chuck Berry what was the role of tara browne in the song mentioned in the beginning ? The lyrics were mainly inspired by contemporary newspaper articles, including a report on the death of Guinness heir Tara Browne. was the song banned on radio? Yes, BBC announced that it would not broadcast the song.
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A Day in the Life [SEP] BBC radio ban
The song became controversial for its supposed references to drugs. On 20 May 1967, during the BBC Light Programme's preview of the "Sgt. Pepper" album, disc jockey Kenny Everett was prevented from playing "A Day in the Life". The BBC announced that it would not broadcast the song due to the line "I'd love to turn you on", which, according to the corporation, advocated drug use. Other lyrics allegedly referring to drugs include "found my way upstairs and had a smoke / somebody spoke and I went into a dream". A spokesman for the BBC stated: "We have listened to this song over and over again.