Okay, so… Taking this out:
<div class="column-half">[recaptcha]</div>
And it works. It must be the captcha… Sorry for the hassle.
With the Twenty Sixteen Theme I still get the same error. Is that what you meant?
If it helps, I have the same formatting on this form here and it works: http://summitathleticclub.com/sponsorships-donations/
