How do I change the twitter handle on my sharing icons?
Changing those would come down to which sharing icons you're referring to.
If you've got a custom built template with a hard-coded Twitter link, we can update those links for you here in Support. Just let me know the name of the template and what you'd like that link to be changed to and we'll take care of it.
Those don't link out to YOUR Twitter, rather they create a link to the mailing that can be posted to the recipient's social media accounts. So that they can share your emails on their platforms.
Taking a look at the most recent mailing in your account, it looks like you have simple text links set up. Those you can adjust the same way you do anything else, by simply deleting the text and recreating the text links like normal. CLICK HERE FOR SOME MORE INFORMATION.