Youtube Feed issue, [Untitled] or "Broken feed"

I’m trying to add the WarThunder channel.

When I add it using the username as the URL is on the videos page i get a feed titled [Untitled] with no items.

When I add it using the channel id as shown on the channel page (also tried this with /videos added to URL) it gets added with a proper title but the last item is from June 2019 even though the oldest in the feed if visited is from January 2020. SIte settings show say Broken feed (551)