The email address can be changed on the 'Settings' of your account, which can be accessed by clicking the username icon located on the top right-hand side of the site:
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Under the 'Security' section you will see the option to change your email address as shown below:

You will then be prompted to change your email address as shown below. You still need to verify the OTP on the initial email address registered before you can proceed in changing your email address so be sure to login on your initial email as well.

After that, you are good to go! Your email address should now be updated to the one you prefer.