Servlet mapping for specific URL not working in Jersey 2

Question

I am trying to use Jersey 2.x and have a servlet call "myapp", configuration on web.xml is as follows

<servlet>
    <servlet-name>myapp</servlet-name>
    <servlet-class>org.glassfish.jersey.servlet.ServletContainer</servlet-class>
    <init-param>
        <param-name>jersey.config.server.provider.packages</param-name>
        <param-value>
            com.private.myapp.resource
        </param-value>      </init-param>
    <load-on-startup>1</load-on-startup>
</servlet>

and have a servlet mapping as follows

<servlet-mapping>
    <servlet-name>myapp</servlet-name>
    <url-pattern>/instance/create</url-pattern>
    <url-pattern>/instance/list</url-pattern>
</servlet-mapping>

when I request to $SERVER_ROOT/instance/create or $SERVER_ROOT/instance/list its return 404

but when I change servlet mapping as follows

<servlet-mapping>
    <servlet-name>myapp</servlet-name>
    <url-pattern>/*</url-pattern>
</servlet-mapping>

then requesting to $SERVER_ROOT/instance/create or $SERVER_ROOT/instance/list response as expected

can anyone tell what I am missing? any help will be appreciated....