Prevent password masking bypass

I am looking for a freelancer to help with a project that involves both implementing and preventing the bypass of a password masking feature on a desktop application. The desktop application is developed in c#. I need someone who has expertise in programming and security to assist in making sure that the password masking feature works correctly and that there is no way for any user to bypass it. It is essential that the project is completed accurately and efficiently so that information is securely stored and protected on the application. I expect the freelancer to be knowledgeable, experienced, and also able to troubleshoot any problems that may arise during the project.