Hello. Thanks for contacting us. This is an error code that we're [url=https://www.bungie.net/en/Forums/Post/255429769?sort=0&page=0]currently investigating[/url] but don't currently have a resolution to yet. We know it's a result of having too many "player sessions" opened. This basically means that when you quit Destiny 2, your session for that time played should go away, but this doesn't happen on Xbox.