Our free training and our shop is separate systems. Applying to start our free sissification training does not create you an account on our store. However, when you create an account on our store then it is strongly recommended to use the same email. Then all your sissy stuff will be in one place :)
Same goes when you want to start one of our premium assignments, even that you can checkout as a guest, it is strongly recommended to use same email. One email gives you one complete experience.
If you need to change your email at any point. Then this has to be done separately as well. First change email in your Academy through the link in your email footers. Usually named "settings" or "change your name/email".
Once email is changed in the Academy, then go and change in the shop as well if you have an account there.