If the product key was not shown in your account you did not register the program previously!
Can you confirm exactly which product you have, please? Your post mentions Sound Forge Audio Cleaning Lab 3 but you also mention the CD "Lab 3". I don't think SFACL3 was ever released on CD so I am not sure where your CD came from.
SOUND FORGE Audio Cleaning Lab 3 "backup dvd".......... Think I purchased from web site. Im in the process of moving. I know I have the label somewhere. Was just hoping for a quicker solution. Thanks for the help.