In April of 2019, Google lost parts of their index. In the following weeks, Google had problems to index new content. It seems that Google is having issues again:
We're aware of an issue that may be causing slight delays in indexing fresh content. We're looking into it and will update when it is clear.— Google Webmasters (@googlewmc) October 16, 2019
Can Google index your web pages?
You have to ensure that Google can index your web pages. Otherwise, your webpages cannot get high rankings. Use the website audit tool in SEOprofiler to check if Google and other search engines can index your website: