Hi,

Please make sure you're using latest version of the theme - version 7.5.1

As I can see you're using old version of the theme - version 7.3.2 - let's go and update it by remove the code at the end of functions.php file like on this image: http://prntscr.com/uon4qx 

After that, do following this guide to get auto-updates the theme: https://pencidesign.ticksy.com/article/15633/ - please do all 4 steps there.

When it done, use this plugin to add your custom avatar to author box:

https://wordpress.org/plugins/wp-user-avatar/

Check more here

Best Regards,

PenciDesign