summer work - copyright clearance

Just a short letter requesting permission to use Olly Murs' song "Dear Darlin". I sent the letter to SYCO music which is owned by Simon Cowell and I managed to find the address after some research. I didn't get a reply however this isn't the song my group and I will be using, it was just an option and its always good to practise because I will be sending a letter in the future to request permission to use someone's song for our project.