Geo/search by IP always returns 'no location associated' error



I have noticed that when I try to use the geo/search REST API method with an IP address as the criteria, the result always returns an error stating there is no location associated with the IP. I understand that might just mean exactly what it says, but I get the same error response when using the sample IP ( address in the Twitter REST API documentation for that endpoint ( I would expect that example IP address to return a result? I have not been able to find any IP that will return a result from this endpoint.

Is this still supposed to work? I don’t see anything in the documentation that says it’s deprecated etc. Are there any known issues with using this endpoint?