Hello,
I am a computer engineer;
I glad to do your job.
I am an expert in Information Security, Web Security, Network Security, also web programming (PHP, ASP) , Programming (JAVA, jsp, C#, ..), Mobile ( android ,J2ME) , node.js, database(MySQL), web service (soap, web api ), CMS ( WordPress) and Framework ( code igniter and Laravel)...
you will get strong authentication mini system with required database as you described I had already have otp implementation on asp.net and another on php so I can do it what you want
I will give you the best solution due to my experts in security developing using php and asp.net
Only chat with me to discuss more details .. I will a demo to you before you have to accept my offer
My offer is best to you with my experts and commitment ...
I am interested in your project and wish to do it ..
Best Regards