Page Break effect Sitemap Generator

Hi Everyone

I use “Google XML Sitemaps” auto to create my sitemap.
But I discover that google search can not index content if it in page break start page 2.
My website address example
http://domain/postname/
http://domain/postname/2
http://domain/postname/3

the page 2 and 3 can not be index in google.

How do I fix this issue?

https://wordpress.org/plugins/google-sitemap-generator/