Asking in the forum since it might be helpful for others.
Historically the email you use for Upwork was directly linked to PayPal. My Paypal uses an ancient email address, so I had to use the same address on Upwork.
Now that there is a new connection method, can I change my Upwork email address?
Your Upwork and Paypal email addresses should match as noted in this help article. You can check out this Paypal help article for more information on how to update your Paypal email address. Once everything is updated on your Paypal account, you can start updating your Upwork email address.
If you need further help, please don't hesitate to reach out!