On step 4, the plugin returns to step 1 without copying content

I'm trying to copy content from one site to another. On step 4 of the process, the plugin returns me to step 1 without actually copying the content.

On step 1, I select Custom Post Type. On step 2, I select the site and the post type. On step 3, I check one of the posts and click "Add item to the list." On step 4, I select the site I wish to copy it to and click "Add site". When I click "Next Step >" it returns me to step 1 but saves all of the form inputs that I just entered.

I checked the apache error log, and didn't see any errors. I also don't get any javascript errors in the console.

I initially tried this for a custom post type ('acf' from the Advanced Custom Forms plugin). When it failed, I tried again with a standard Wordpress page but was still unsuccessful.

I'm using the latest version of the plugin and WordPress.

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