I formatted on my pc and the email with which I registered years ago I canceled it and they sent me a code to that email and I can't get it.... .. Thanks for your help
I assume you have changed your email address and that is the cause of this problem.
Go to your Magix account, log in using your old email address and go to My products. Find the listing for your version of Sound Forge and your serial key. You might also wish to deactivate any listed installations of SF you no longer need. Also, whilst you are accessing your account go to User data and update your email address to your new one.