Weekly check this important task of SEO "Broken Link Checking"
As I already said you should make fully search engine trusted.
If you have broken links this will confuse search engine and search engine think your site is under construction so they ignore during crawler update.
To check broken links
Go to webmaster tools --Crawler -- Crawler Errors
See here https://ibb.co/fuWSbx
Check how many crawler errors show not found URL
Check this https://ibb.co/gKiqwx
As I have 1262 Broken Links Too many Broken Links This will Confuse Search Engine and They Ignore While Crawler Update.
So let's Fix It Check Your Sitemap and Update Your Sitemap, Generate new sitemap and upload it to your host or If you are using Yoast or all in one SEO plugin they generate auto 24 hours sitemap. So broken links will be removed from the sitemap.
Now go to back to webmaster tools and re-submit your sitemap. See here https://ibb.co/dWEoGx
Now Go back to Crawler Error Option in Webmaster Tools and Click Mark all as Fixed See Here https://ibb.co/mpH8Gx
Do this task weekly and test it weekly, So this increases your trust with search engine otherwise they ignore your site and keywords while crawler update.
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