Not working in my website

One of my website is strictly forum website which is powered by wpforo PLUGIN.

I want to display the latest Forum posts from this feed link in the sidebar widget of this website.

But when I do that, what I see is this;

Sorry, some part of this feed is currently unavailable or does not exist anymore. The detailed error is

https://forums.allschool.com.ng/community/recent/feed/ is invalid XML, likely due to invalid characters. XML error: > required at line 4, column 56

(Only you are seeing this detailed error because you are the creator of this post. Other users will see the error message as below.)

Please can you help me fix it?

The page I need help with: [log in to see the link]