Laravel SEO sitemap generation stuck!

I am completely losing my mind over this and desperately need some help. I've been trying to implement 'Dynamic XML Sitemap for Laravel & All Websites' to really boost our Laravel SEO for our new SaaS, as proper indexing is absolutely critical for us right now.

The problem is, the sitemap just isn't auto-updating or regenerating properly. I've configured everything according to the docs, or so I thought, but changes on the site are just not reflecting in the sitemap. I've spent hours debugging, and I strongly suspect it's either a caching issue that I can't seem to bust, or some weird cron job misconfiguration that's preventing the regeneration command from firing or completing correctly. I'm completely stuck and running out of ideas.

Here's what I'm seeing in the logs:

[2023-10-27 14:35:01] local.ERROR: Failed to regenerate sitemap.xml. Check permissions or configuration. {"exception":"[object] (RuntimeException(code: 0): Sitemap generation failed at /app/SitemapService.php:123)"}
[2023-10-27 14:35:05] local.INFO: Sitemap not modified since last generation. Skipping update.

Has anyone faced similar issues with dynamic sitemaps in Laravel, especially regarding cron jobs or cache invalidation? What on earth am I missing here?