I think you meant you updated the email address in your client's return but it's not showing up in Intuit Link. That's because Intuit Link pulls the data from the details saved under Clients instead of what's under Tax Returns and there's no synchronization between the two after the creation of the return.
To edit your client's particularly for Intuit Link, you will need to go to Clients, on the line for your client, click on the dropdown for View client & return, and select Edit client. Once you save the changes, the new email address will be reflected in Intuit Link and be used for future communication. When you send the request, Intuit Link may, however, prompt you whether this new email address instead of the existing one should be used. Just select the new email address and hit Continue.
If this is a client who already had responses and documents saved in Intuit Link previously, changing the email address will cause your client to lose access to those entries (although it won't affect yours). In case this applies to you, please come back as there is a different process to follow.
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When you create the request again to be sent to the new email address, it should prompt you which address you want to use.
On the Intuit Link dashboard, even before creating the new request, it should show the new email address if the update you made under Clients was, indeed, saved correctly.
If you do not see the new email address on the Intuit Link dashboard, you should follow the process outlined above again to check under Edit client that the new email address is already there. And if the new email address is there but Intuit Link does not prompt you at the creation of the new request which email address to send it to, you will need to contact Intuit Support because something is tripping up the system.
Still an AllStar