Use Google’s API for instant indexing on key pages. For bulk, try paid...

https://www.ranktracker.com/blog/best-website-indexing-tools-for-seo/

Use Google’s API for instant indexing on key pages. For bulk, try paid tools—some offer 60 credits for $29. A warning: "crawled but not indexed" is a page quality issue, not a technical one. Don’t force-index thin pages; improve quality first, then push.