Search endpoint not working for some objects in API v3.1

Hi,

I am trying to perform /Search?updated_after_utc= on some objects like LeadSources, Teams, TaskCategories etc to get the records updated/created after specific datetime. 

example postman query: 

https://api.insight.ly/v3.1/LeadSources/Search?updated_after_utc=2019-11-11T12:05:52.960Z

But in response I am getting either 404 Not Found or 400 Bad Request "The value 'Search' is not valid for Int64."

Can you please verify that? And if it is the case that /Search endpoint is enabled for some selected objects only than can you please list the objects that doesn't support this functionality?

Thanks.