Hi, How do I get my Hashnest private key?
Thank you so much!
Thank you so much!

What do you mean by that, there are private/secret keys from their API is that what you're referring to?
If you mean the bitcoin private key to your wallet then you can't as that's not how that sort of wallet address works as they have to own your deposit/withdraw address to ensure you don't buy stuff and then instantly withdraw that money and also to mean that there doesn't have to be fees paid on microtransaction if you do a trade on their site.
I'm talking about the private key of the bitcoin wallet. Because I made a transaction 20 days ago, and it haden't been confirmed yet.
I need the key to perform the double spending process.
This is the transaction: https://btc.com/e03693df9eeec504e6b7d1959e1f802f1e80226a145721d75919ca4523079e0d