There are a few reasons that could factor apply to your card or item:
Balancing Phase: Cards recently introduced into the game, such as those found in new sets, will initially have trading locked during the Balancing Phase (see above). This locked period helps us ensure each card is well balanced before it becomes tradable on secondary markets, making it simple for players to understand that cards they purchase individually can no longer be buffed or nerfed by us and that their scarcity is fixed. The locking period also ensures we never compete directly with secondary player markets, allowing for a healthy separation by minimizing the dependability players have to place with us.
Core cards are the exception here. Core cards minted to the Ethereum network will always be tradable, but as an “open” card set they are able to be balanced over time to ensure the overall balance of the game is kept in check. At the time of writing, these are currently the only cards that can both exist on the blockchain and be altered. As the game’s base set, these cards are designed to be an anchor point for all other cards to bounce off, and they need to be tweaked from time to time to ensure the game remains balanced.
Immutable X minting: During Season 1, all Items (excluding chests and draw tickets) are usable in-game from purchase but will not be tradable or minted until the release of Immutable X, our item exchange on the Ethereum network. This platform will greatly reduce the cost of token minting and user to user trading, while still providing true ownership for players.
Season 1 chest trading: Seasonal chests may be traded once their seasonal sales period is over and all other conditions have been met. They do not require Immutable X minting to become tradable. It’s important to note that only unopened chests are tradable as – once opened – a chest transforms into individual card packs, which become subject to Balancing Phase and Immutable X minting conditions.