UniForm send error

I’ve just launched a new site, and I’m using the UniForm plugin, as well as the official Kirby email plugin for the contact form. I’ve just sent a test message and I’m getting the following error when I click the submit button:

Fatal error: Call to a member function send() on array in /app/site/plugins/uniform/lib/UniForm.php on line 563

The form is submitting because I receive the email, so I’m not sure what’s going wrong here. Does anyone have any ideas for a fix?

Could you post your code, pls? why are you using both plugins?

I thought I needed to use the email plugin so that I could send it with Mailgun, but it looks like I just needed to add the config and didn’t need the plugin itself. Removing that fixed the problem.