In general, [REST](https://community.denodo.com/docs/html/browse/latest/en//vdp/administration/publication_of_web_services/publishing_rest_web_services/settings_tab_rest) Web Service URL with JSON format will return the complete result set in a single web page but for HTML format by default, it will return 25 rows per page. Hence, in order to [increase that row size](https://community.denodo.com/docs/html/browse/latest/en//vdp/administration/restful_architecture/restful_web_service/input_parameters_of_the_restful_web_service), you can either use the [$count](https://community.denodo.com/docs/html/browse/latest/en//vdp/administration/restful_architecture/restful_web_service/obtaining_the_number_of_rows_of_a_result_set) in the URL or you can modify the default setting available in the web.xml.template located at <DENODO_HOME>\resources\db\wsgenerator\restfulws and restart the Denodo servers.
If I face the same issue, I would check the log files **vdp.log and vdp-requests.log** located in path <DENODO_HOME>\logs\vdp by changing the log level to ‘**INFO**’ in order to debug the issue.
For more infromation, you could refer to the KB article [How to log the requests issued on a VDP server](https://community.denodo.com/kb/view/document/How%20to%20log%20the%20requests%20issued%20on%20a%20VDP%20server?category=Operation#:~:text=The%20Denodo%20Virtual%20DataPort%20Server,log.).
Hope this helps!