Getting Permission to use Material

In order to use a particular artist's material, we have been told how important it is to get permission from the artist's management so that we can incorporate their song into our pop video. Therefore after independent research, I managed to get the email of singer's Charli XCX and Yuna's management company. Here's a screenshot of the email I sent to them:

This message is to Charli XCX's management company:

And this message is to Yuna's management company:

At the moment I am waiting for their reply and hopefully we will receive permission from at least one of them!