Thank you for your quick response @vaakash!
We use Elementor on the site, so I had to:
– open the page in edit mode in Elementor
– update the feed title in the widget settings
– save the page in Elementor.
This removed the error messages.
I cannot see that the RSS feed is updating yet, but as this is on a dev site there could be multiple reasons for that 🙂
Kind regards,
Øyvind