Suggest endpoint in the Search REST service in SharePoint 2013

I was trying to build a search box with suggestions as user typing using this endpoint "/_api/search/suggest" documentation in https://docs.microsoft.com/en-us/sharepoint/dev/general-development/sharepoint-search-rest-api-overview.

However it doesn't seems work for me, does anyone came across this and know what might went wrong for me? Thanks for help.