how does pagination work in hotel search? I got pagination result like below:

   "pagination": {
        "currentPage": 1,
        "pageGroup": "EXPEDIA_EXPANDED",
        "nextPageStartIndex": 11,
        "nextPageNumber": 1,
        "nextPageGroup": "TPI_EXPANDED"
    }

On my next query, I set page_number field to be 11

“page_number”: “11”

The result of this query is the same as the original query where page_nunmber is 1:

“page_number”: “1”

Also, what is pageGroup? The given Example does not show this field.