The available information only shows that a specific Roblox Digital Card code obtained via Microsoft Rewards can become invalid and that, in that case, Microsoft Rewards support may refund the points so a different Roblox gift card can be redeemed instead. It does not state whether a particular “400 Robux” reward option or code type is permanently removed or temporarily unavailable, nor whether it is being replaced.
For a Roblox reward that is missing or has changed, the supported action is to contact Microsoft Rewards Customer Support so the Rewards team can review the situation and either assist with the existing order or provide an alternative (such as a refund of points so a different reward can be chosen).
To review or re-access any existing Roblox reward orders and codes, go to the Rewards dashboard Order History and open the order details for the Roblox Digital Card in question.
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