Jallow was born in London and grew up in the Stratford district of the city. He eventually moved to Peterborough in Cambridgeshire. He is of Gambian descent and was raised by his mother, who emigrated to England when she was 25 years old. He was raised as a Muslim and is of ethnic Fula heritage. In June 2018, he was arrested in Stratford and charged with carrying a knife in public. Hours after he was released from prison in April 2019, he made a surprise appearance on stage at Canadian rapper Drake's concert in London.