Hello PrdBlackWatch, thank you for getting in touch with us about this.
To quote our Support article on this -
Some of the music we use in our games is our own. However, some titles are licensed and owned by the artists. If you post a video with licensed music on a video website, it may result it a copyright strike from the website. To avoid this, we recommend that you turn off the music in the game if you plan to record a gameplay sequence.
Can I ask do you monetize your Rainbow Six Siege videos on your channel? If so your video will not be blocked and these notifications are only meant to inform you that another entity, in this case BMG has wholly monetized this content within the system. We advise against disputing these claims unless you have a direct license from the claim owner BMG.
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