Check your sitemap.
Get indexed.

A sitemap is a recommendation, and contradicting yourself is the risk

A sitemap does not make pages rank and it does not guarantee indexing. It is a discovery aid: a list of URLs you consider worth crawling, with optional hints about when they last changed. Search engines treat it as a suggestion, weighted by how much they trust you.

That framing matters, because it explains where sitemaps go wrong. The damage is rarely a missing sitemap. It is a sitemap that contradicts the rest of the site.

Consistency is the whole job

Every URL in a sitemap is you saying "this is worth indexing". So each one should return 200, be canonical to itself, be crawlable, and not carry a noindex. Listing a URL you have separately told search engines to ignore is a contradictory signal, and it erodes trust in the rest of the file.

The usual offenders are noindexed pages, URLs that redirect, non-canonical variants such as parameter and pagination URLs, and pages blocked in robots.txt. Each is you asking for a crawl and then refusing it.

The mechanical limits

A single sitemap file holds at most 50,000 URLs and 50MB uncompressed. Past that, split it and reference the parts from a sitemap index. Splitting by content type is worth doing well before you hit the cap anyway, because it turns coverage reporting into something diagnosable: if products index at 94% and blog posts at 40%, you know where to look.

lastmod is only useful if it is honest. A build process that stamps every URL with today's date on every deploy is telling search engines nothing, and they learn to discount it. priority and changefreq are effectively ignored by Google and are not worth arguing about.

How UtilitySEO handles this

Sitemap and indexability checks run as part of the site audit, and the fix list flags the contradictions specifically, since a sitemap that disagrees with your own canonical and indexing signals is a more actionable finding than a raw URL count.