I'll just leave you with this section from their support article: [quote]Player Behavior that can lead to Account Bans or Restrictions Bungie regards some behavior to be in breach of the license agreement that governs Destiny, and therefore potentially subject to access restrictions or bans. This behavior includes, but is not limited to: Connecting to the Destiny game service with any of the following: Modified game software Modified game assets Modified hardware Modified console firmware Modified operating system files including emulators and virtual machines Using an external program to modify the operation of the Destiny game software, such as: Trainers, mods, cheats, aimbots, or autofire. User mode or kernel debuggers Graphics hacks Sending malicious network traffic to Destiny servers or other Destiny players Using an external program or device to automate gameplay or circumvent idle detection. Modification or interruption of Destiny network traffic with intent to disrupt the experience of other players or to gain an advantage in the game. Intentionally deriving gameplay benefit from another user’s behavior in the above categories. Unauthorized access to Destiny software or downloadable content (game piracy). Impersonating a Bungie, Microsoft, Sony, Blizzard, or Activision employee. Online behaviors disruptive to the experiences of others, such as: Hate speech, griefing, or message spamming Habitual unsportsmanlike conduct Habitual quitting or idle behavior in matchmade activities Intentionally deleting another player’s items or characters by logging in with their account credentials Habitually quitting from a Competitive Crucible match will result in a 30-minute Crucible restriction Additionally, Bungie may issue restrictions or bans to accounts that have consistent unstable connections when playing Destiny, as this negatively impacts other players. For steps on how to stabilize your network and connection quality, please follow the Network Troubleshooting Guide. Please note: Bungie reserves the right to permanently ban Destiny accounts or player hardware that have been confirmed as repeat offenders. Activity bans or restrictions may be escalated to device bans after multiple confirmed offenses.[/quote] I can't say for certain what caused it; only Bungie knows that, and like I said, they won't tell you why. But you can look through this and if anything you run falls under these categories, then that's probably what did it.