Email address on desktop and laptop

When you're on the two computers I'm going to presume you're using a browser and the web UI and not an email client, right?

Go into Settings, then More Settings and click Mailbox.  Click your email address to open up the details on the right side of the window.  Chances are you'll see the ATT-Yahoo Mail string in there.

Thanks for the suggestion but when I looked at the settings, the correct email appeared. So still don't know where that is coming from. Might just have to switch to gmail!

And you clicked on the Mailbox, clicked on your email address and then looked in the right side of the window?  Because that's where your "From" name comes from.

My right hand doesn't look like that. It looks like this:

Sigh......do you see where I put a #2 marker and told you to click there?  The page you show is what you get until you click the email address (#2).

My sincere apologies for making you sigh, oh great ace guru.  I obviously did not read your original message with the proper amount of attention that it merited.  Please accept my regrets for having made you repeat your instructions.  Just another case of UBD.

Thank you for resolving my issue.

🤣  Well, if we're counting, I mentioned that detail in all three of my comments, thus the sigh.

But hey, as long as you got it solved I'm happy.