My picture in my profile is sideways. So, I tried to send an Email to Udemy. Sadly, I don't know if they received my Email. To be honest, I'm considering posting my course on Youtube, instead of Udemy.
btw. As I found your image online it looks like maybe the problem is the orientation of the photograph, or it might be related to its low resolution. I suspect that you tried to upload this picture here:
This gentlemen here seems to suffer from the same low-resolution photograph turning sideways problem:
And he also has an upright picture instead of a "landscape" version of it. You can crop the image to be in portrait mode with.. well.. paint.. basically:
This should fix all your problems on the image.