Hello,
Thank you for contacting the support and we regret the inconvenience caused.
I checked your sitemaps and it is working just fine. It is properly accessible with Bingbot as well: https://i.rankmath.com/IMWjVr
URL discovered but not through sitemaps is not an issue, it only means that Bing has already discovered the posts/pages/CPTs but not through the sitemap.
It is possible that Bing is crawling the website through other means like the internal links on your website and not through the sitemaps. As a result, the crawl budget for your website is exhausted, and Bing is not able to discover the URLs through your sitemap.
As long as the URLs are getting crawled, there’s nothing to be worried about.
However, could you check your Bing Webmaster Tools account to see if there are any errors listed?
Looking forward to hearing back from you.
Thank you.
Hello,
Since we did not hear back from you for 15 days, we are assuming that you found the solution. We are closing this support ticket.
If you still need assistance or any other help, please feel free to open a new support ticket, and we will be more than happy to assist.
Thank you.