A fix for this issue will be available on November 8 at the launch of Northdark Reaches. Due to this, the Last Chance Vendor for Masquerade will be extended until November 17. This will allow players to use their Masquerade currency. Thank you for your patience.
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We are aware and actively working on an issue where some players or some characters within an account are unable to purchase items from the Masquerade of Liars event store, boon unlocking, and Campaign Store. We apologize for the inconvenience and hope to have a fix in soon.