Contact Form Not Sending Messages to Specified Email Address

Hey,

I have specified an email address on the contact form supplied by the upfront theme, but when I try to send a message from the form I receive this error: https://www.dropbox.com/s/whxx9ey7mrz2r94/Screenshot%202016-09-06%2021.29.29.png?dl=0. This is the PHP error I receive when I inspect the page https://www.dropbox.com/s/dhbcwmt0xtfhw9q/Screenshot%202016-09-06%2021.32.29.png?dl=0

Any idea what this issue is and how to fix this?

Thanks!