Best answer by Mathis
"Anyone" here (You seem to have posted your question as a private conversation - in that case, only Company representatives will be able to see your post). Many of our regular forum users are happy to help with such questions, so feel free to post future questions publicly.
Now, let's take a look at your issue. Your profile picture is currently 2407 × 2094 in size - iTunes is grabbing your profile picture for your podcast rather then the artwork of each individual track and that is the one that needs to be 1400x1400 (with a maximum size of 3000x3000). Thus, once you have updated your profile picture, you should be good to go.
Hope this helps - let us know if you need further assistance though, happy to help.