Why is My Auto-Updating XML Sitemap for Laravel Generating Severe Indexing Issues? Stuck!

I am absolutely tearing my hair out trying to figure out what's going on with our sitemap, and I'm completely stuck. This is causing serious issues for our site's visibility, and frankly, I'm desperate for some guidance.

We've been using the 'Dynamic XML Sitemap for Laravel & All Websites (Auto-Updating & Future-Proof)' because the promise of an auto-updating and future-proof solution for XML sitemaps sounded like exactly what we needed to ensure our content was always discoverable. However, despite its 'auto-updating' claim, we are facing severe indexing problems. New content, sometimes hours or even a day old, isn't getting picked up by search engines. Worse, old, deleted, or irrelevant URLs are stubbornly lingering in the index, leading to a frustrating user experience and diluted SEO efforts. It feels like the sitemap isn't reflecting the true state of our website, and it's causing significant indexing issues across the board.

I've tried a number of things already, but nothing seems to resolve these critical indexing problems:

• Manually regenerating the sitemap via our admin panel.
• Verifying that our Laravel cron jobs for sitemap updates are running without errors.
• Inspecting the sitemap.xml file directly to ensure the structure is valid and URLs are present/absent as expected.
• Using Google Search Console's URL Inspection tool and sitemap submission features, which often report 'discovered - currently not indexed' or similar for new content.
• Checked robots.txt to ensure no accidental blocking.

Has anyone encountered similar indexing problems with this specific tool or dynamic sitemaps in general? Are there common misconfigurations I might be overlooking? Any debugging strategies or specific areas within Laravel or server setup that I should investigate further to finally get our XML sitemap functioning correctly and resolve these critical indexing problems once and for all?