ip api on c#

I am looking for a skilled developer who can create an IP API on C# to retrieve specific IP information for my users.

Requirements:
- Retrieve Geolocation, ISP, and Proxy detection information
- Improve the speed of the current API (api.ipify.org)

Skills and Experience:
- Proficient in C# programming language
- Experienced in working with APIs and retrieving IP information

Deadline:
- The project needs to be completed as fast as possible.