Non logged in users (casual visitors) not able to type in chat


I've installed the Chat plugin on our site. Everything seems to be going well, but non logged in users are not able to chat even though I have chosen this option in setup. The bottom corner chat opens & shows conversations but does not contain a text box to type in.

I am using the Themeforest Salutation theme & fear this may be the issue.

The site is located at