Modern day slavery.
They use candidates for free labor - do not waste your time.
Even if they don't plan to hire you,
The "tests" they give is actual labor they cannot do themselves with long specific requirements, you would get an actual ticket, be asked to submit a repo with a full solution, and after you finished the "test" and submitted the task they needed, they would ask you questions that have nothing to do with it.
You would get no feedback\solution\explanation of your mistakes in the task - cause they don't have any : they never planned to hire you, they don't know the solution, they just take advantage of people.
Highly unethical and borderline illegal.