Old email for retrieving my licence. Need to set to current

I just installed windows 10 on my new ssd and am moving everything over. I was terrified that the single most useful app on my computer was gonna be rendered useless as no matter what I did I couldn't reactivate opus directory. I tried my old email and it worked. How do I fix this so it uses my current email if something should go wrong? Thank you.

You can update your details including your email address from the My Account page on our website.

Thank you so much!