The weekend saw the final 13 - including wildcard Monica Michael - perform in front of the judges and studio audience in the first of the live shows.
However, Bupsi and Alien Uncovered didn't do enough to be saved on Sunday's live double elimination results show.
Bupsi was the first act to leave the competition having received the fewest votes of the night. Bupsi, who was mentored by Simon Cowell, said she was grateful for the opportunity as she bowed out of the show.
It was then between Alien Uncovered and Kiera Weathers, who faced the sing-off.
While Cheryl Fernandez-Versini saved her group Alien Uncovered, Rita Ora chose to save her girl Kiera. Nick Grimshaw said his opinion on the two acts had changed based on the sing-off and he chose to save Kiera.
With head judge Simon the only one left to vote, he chose to save Kiera and told the studio audience that he was making his decision based on the sing-off, although he admitted: "I'm unhappy with this decision - though it's the right decision."
However, many took to social media after Simon's decision as viewers heard him say he was sending home Alien Nation, rather than their actual name, Alien Uncovered.
Cheryl said she was "in shock" to see her girl band Alien Uncovered leave the competition in the first week.
The X Factor airs every Saturday, followed up by the results show on Sundays.
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