Here is how to change your profile picture.

First go to the top right and click on the arrow After that, go to "My Account"

Now you will see your name and a blank profile picture

Press the "Edit" button and now you can change your name and profile picture

If its not working, turn off any adblocker. Since i use Brave Browser, i had to turn off my shield to add my profile picture. Hopefully this can help you out!