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Fans are asking questions again after Justin Bieber and Selena Gomez were spotted in the studio together. 

The on-again, off-again couple was spotted at the Hit Factory recording studio in Miami late Tuesday night -- a hangout that was documented on Twitter by Bieber's protege, Madison Beer, who posted photos with both inside. 

New York Daily News says the Biebs has been recording at Hit Factory for the past week, and Selena headed straight there to see him when her plane touched down.  

Since the two refueled rumors about their relationship after reuniting in Texas last month, reports have surfaced that Justin and Selena have been collaborating on a song called "Unfamiliar." 

Justin tweeted on Wednesday that he has "some big things planned" and is "making the best music [he] has ever made." 

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