Not helpful, as the OP should still recieve the boost item (as stated in your linked post) but not be able to use it.
Are you looking for the boost on an older character that may have a few things in your inventory? Try clicking on the cog wheel at the top right of your inventory box and seperate the Shared slots, since the boost is in one of them and can not be moved from it. You can also search your inventory. If you know for sure you don’t have it, I’d submit a support ticket.
I did support ticket already. They linked me that post and just told wait.
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