Unconfirmed Blockchain Status Need Help,
Transaction invalid: some outputs that it attempts to spend have been already spent or are no longer valid.
This is the message appearing on the Summary report from block chain. It was process last January 08,2021 and the result until right now is Invalid and no progress at all. How to fix the issue.
Thanks in advance...
That message means that the sender created two transactions that attempted to spend the same coins. This is called &quot;double spending&quot; and is not allowed. One of the two transactions has to be marked as invalid by any Bitcoin node that sees the two. I believe most Bitcoin nodes will initially set aside whichever they received last. Over a short time time, the network as a whole comes to a common view about which transaction is accepted (so some nodes may change their decision after a few tens of minutes from their initial decision).
The transaction that you are looking at has long ago been determined, by all participants in the Bitcoin network, to be the incorrect one of the two.

How to fix the issue.

You can't.
If you are the creator of the transaction, you should be able to find the other transaction where you spent that money.
If you are a recipient, you just treat that transaction as if it never happened, you were not paid.

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