I posted about this a few months ago. Through some sheer brain dead dumbassery on my part, I sent 3.32 ETH worth $9000 to an Elon Musk crypto scam a few months ago.
My Coinbase account will show it as a withdraw, but it was lost to a scam.
So when Coinbase sends me a 1099-K or whatever the tax form is, how can I allow for this as a LOSS, not taking a profit?
As a general rule, you should have a police report that you have been defrauded by fraud and your solicitor or tax adviser will gather all the necessary documents.
Your tax return will have to be amended as a result of this incident.
I am not sure that the loss from this fraud will be a tax loss for you.