I've noticed a lot of avatars from people that must be quite large, and all we are seeing is a thin vertical strip of it.
Many forum software programs limit the size of the avatar, this one may and it's not set.

In either case, if using Windows, there is a program called Paint. You can load your picture and resize it to make it fit better as an avatar. I'm sure Apple computers have a similar program. If mobile, you can use an app like Pixlr Express to resize your avatars if needed.