RSS feed for GC Testimonials

My site is avelim.org.il

I am using GC Testimonials plugin http://ww.wp.xz.cn/plugins/gc-testimonials/

I have many testimonials created by this plugin on my site.

I wanted to create an RSS feed for the testimonials using the plugin Custom Post Type RSS feed http://ww.wp.xz.cn/plugins/custom-post-type-rss-feed/

I installed the plugin and activated it. The RSS feed is not created. Can you help?

https://ww.wp.xz.cn/plugins/custom-post-type-rss-feed/