How do I change the email address thats linked to my jsp?

I dont have access to the email address that this one is linked to anymore, luckily I remembers my jsp password lol

If you no longer have access to the registered email, your only option to change the email would be recovering your account using the first option: https://forums.d2jsp.org/recovery.php
Here's a guide if you get stuck: https://forums.d2jsp.org/topic.php?t=70679141&f=34