Selling / Buying / Trading text has been updated to be more precise:
You are not allowed to sell/trade/buy accounts, items, coins or other goods or services to/from other users.
The send coins and gift items features available on our website are to be used for, and only used for, gifting coins or items. Buying or selling items, coins or accounts is not supported and will result in permanent trade bans, preventing you from sending or receiving coins, cosmetic box items and lucky box items (including golden tickets).
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