Read through your last post (including my bits in quotes) again.
Now think. Join the dots! You dont see anything a bit odd?
Its not magic at all its not his money its the OP's money.
The contract is void because one party has not delivered.
But that party decides to keep the money anyway.
He refuses to return that money.
Its not his money.
The OP did not authorize this.
To all intents and purposes the "seller"
is a THIEF.
You can dress it up in whatever language you like to justify this apparently legit business practice but its still stealing of monies not belonging to them.
STOLEN
THIEF THIEF THIEF !!