Hi Emeline,
Thanks for contacting Syncfusion support.
We have analyzed your code example and we are able to reproduce the reported issue from our end. Because the properties(paging.AllowPaging(true), paging.PagerPosition(Position.BottomLeft), paging.PagerStyle(PagerStyle.DefaultAndAdvanced)) you have mentioned in pageSettings which are not defined properties of pageSettings API of ejGrid control .
In default, if you enable allowPaging property it will take default page size as 12 also you can customize the page size through pageSize property of pageSettings and the pager shown in bottom left side. If you want to customize the pager then you can use the pager template in your sample.
Refer the online sample for pager template.
Refer the help documentation.
If we misunderstood your query then please get back to us.
Regards,
Thavasianand S.