Same as what others have said, their tech team is apparently too busy to even talk with the talent they are trying to acquire.
They ask you to develop a Finite State Machine, which is a curve-ball for any programmer unfamiliar with the mathematical concept, but it becomes easily apparent what you have to do after some research.
The development manager isn't even involved in this process, makes one wonder if this is even a real company, or if it's some strange machine learning data collection project in which you do not get paid for your time.
Don't waste your time with them, the requirements for their role literally changed after the project was complete.