First random number is alway the same

I am trying to write a simple program. I heard in C++ that there are existing functions that are better than rand() (to make random numbers). I am talking about classes from #include <random>. My program goal is to make random numbers.

This is my code:

int randomSpawn()
{    
    unsigned seed = time(NULL);
    std::default_random_engine rng(seed);
    std::uniform_int_distribution<int> d(1, LENGHT);
    
    srand(time(NULL));

    std::cout << d(rng) << std::endl;
    std::cout << rand() % LENGHT << std::endl;

    return rand() % LENGHT;
}

The problem is that the first value is always the same - 17. LENGTH is equal to 30.

So, the oldest version making random number is working - because it displays a random number, but the new version doesn't work because it always displays 17.

I tried to move the seed definition to another part of code, but it didn't help.