Ajax loader after submiting a message on Contact Form 7 not showing up

Hi,

After clicking “submit” on the contact form 7 on the “Contact” page there is no spinning wheel or progress bar. This is having the effect of users hitting submit multiple times and often receiving 3-4 versions of the same e-mail.

Is there any way to add or restore this functionality? It seems that the theme is overriding the form appearance?

I tried deactivate all plugins to see if there was a conflit with contact form 7 but the problem persisted, then I changed the theme to Twenty Fifteen and this functionality was showing up again.

My website with the form its this: http://www.mobissom.com.br/contato

Thanks for your help!