We are build an RSS feed on our website but when opening the URL through Safari and chose to open using News app, the app will try to load it but then said "Couldn't add feed" - no further information.
We tested on Podcast app and worked, Feedly app also worked. Worked fine on Andorid devices and on Outlook in windows.
We follow apple guidline from the following page
We have also validated the RSS feed using the online RSS validator.
Any help will be appreciated.