Securing exe

I have a desktop application written in c#. I want to secure it. I have used the confuserex, themida and crypto obfuscator to obfuscate it. But they seems to be breakable. Currently we are using crypto obfuscator. Our requirement is 1. Demonstrate and document how you can break our current application. 2. Proving better obfuscation and encryption solution to secure it. I will provide our exe on request. Please note after securing with cryptoobfuscator, antivirus detects exe as malware/virus. Note: Please bid only if you are expert in this area and already worked on similar projects. No payment for partial work or attempt.