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I am not with Laminar Research; just a flight simmer.
This is not the forum to solve your problem. Others are having the same problem with this mob. You need to go back to the seller of the software.
Have a look at the comments and answers given in the following link at https://questions.x-plane.com/19886/plane-11-wants-insert-product-key-even-have-done-that-before
You will find a comment from Laminar Research as well.
Personally I think you have been "dudded"
Good luck in solving your problem.
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