Possible Federation Problem?

In a lemmy.world support post https://feddit.uk/post/788935 it's noticed that some comments are not appearing here at feddit.uk.

Comments made in a community on lemmy.world not appearing on feddit.uk.

https://feddit.uk/post/809693

https://lemmy.world/post/1995177

But they do show over at lemm.ee

https://lemm.ee/post/1801137

Maybe more of a feddit.uk issue?

Any one got any thoughts?