u/Expert_Ad_140

A Springer editorial assistant sent my paper back quickly after i submitted it requesting me to add the corresponding author in both the manuscript and submissions. i tried to check if i failed to mark the corresponding author, nothing's wrong, it looks like i added it. so i tried to see if there's any formatting problems around how i wrote corresponding author by screenshotting it to chatgpt and asking, it couldn't find any errors as well. i am the sole author so there aren't more complicated stuffs as having to confirm I'm the corresponding author via email as well. can anyone tell what the heck I'm supposed to do?