Simple WhatsApp Webhook Development in C# (Source code)

I am seeking a freelancer to create a simple webhook for WhatsApp in C# , all wrapped in a neat project source code. This will be hosted on a Windows Server. The main functionality that I'm seeking is for the webhook to receive messages through WhatsApp. This must be developed to the standards of secure and efficient data handling.

Ideal candidate would be someone with:
- Proficiency in C#
- Experience in webhooks development
- Familiarity with Windows Server environment
- Understanding of WhatsApp API integration.

Please detail your experience with these languages and systems when applying.