If you can be able to login, you should be able to edit your email. Isn't that possible on the casino that you are using?
If you can not, contact the casino customer care.
In your case why don't you contact the casino support to see if you can have an email change, because it is still possible to have your email address changed in some cases where you can provide some valid proof.
Changing an email is not possible on my account since I can't prove ownership without my email. I never done KYC on this casino which is why there's no point for me to prove ownership now thy I don't have access on my email.
Just making sure that I'm not doing anything that will violate the ToS unknowingly. Support usually becomes aggressive once asked something controversial such as closure of account that I can't prove ownership aside from login details.
Temporarily lock this thread. I will try to request now.