Unfortunately, items (after they expire on the auction house, after 2 days) do get sent to an "expired" section.They stay there for 10 days and then are deleted from the server. So, if more than 12 days had passed since you sent the items to the auction-house, that's most likely the reason.
If you are
absolutely positive that nobody had purchased them, then maybe there was a server rollback. This happens occasionally due to various, (usually small) reasons. In this case, the diamond blocks would go back to wherever you had them, at the time of the last server backup. If you didn't have the diamond blocks at that time, then you wouldn't have them now.
Personally, I'd check to make sure that my island members didn't have them or use them, and double check my chests. (I've accidentally lost my sword in my chests due to auto-deposit several times
)
Unfortunately, if you can't find them, then they're most likely gone permanently. (I've lost some very expensive items due to server crashes before
, I know how it feels.) But, you might be able to find someone that is willing to help you regain some of your lost items, (especially if you're nice to them
)
Best of luck, -Mango
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