Implementation of the chaotic map to produce (pseudo)-random number

For my project I used Henon map to generate (pseudo)-random number. I used the following code to generate the matrix of (pseudo)-random number.

def generate_by_henonmap(dimension, key):
    x = key[0]
    y = key[1]
    # Total Number of bitSequence produced
    sequenceSize = dimension * dimension * 8
    bitSequence = []  # Each bitSequence contains 8 bits
    byteArray = []  # Each byteArray contains m bitSequence
    Matrix = []  # Each Matrix contains m*n byteArray

    for i in range(sequenceSize):
        # Classical Henon map have values of a = 1.4 and b = 0.3
        xN = y + 1 - 1.4 * x**2
        yN = 0.3 * x

        x = xN
        y = yN

        if xN <= 0.4:
            bit = 0
        else:
            bit = 1

        try:
            bitSequence.append(bit)
        except:
            bitSequence = [bit]

        if i % 8 == 7:
            decimal = dec(bitSequence)
            try:
                byteArray.append(decimal)
            except:
                byteArray = [decimal]
            bitSequence = []

        byteArraySize = dimension*8

        if i % byteArraySize == byteArraySize-1:
            try:
                Matrix.append(byteArray)
            except:
                Matrix = [byteArray]
            byteArray = []

    return Matrix

Before I use this code in my production I test the randomness by NIST Test suite from this but got this result:

Eligible test from NIST-SP800-22r1a:
-monobit
-frequency_within_block
-runs
-longest_run_ones_in_a_block
-dft
-non_overlapping_template_matching
-serial
-approximate_entropy
-cumulative sums
-random_excursion
-random_excursion_variant
Test results:
- PASSED - score: 0.525 - Monobit - elapsed time: 0 ms
- PASSED - score: 0.999 - Frequency Within Block - elapsed time: 0 ms
- FAILED - score: 0.0 - Runs - elapsed time: 1 ms
- FAILED - score: 0.002 - Longest Run Ones In A Block - elapsed time: 0 ms
- FAILED - score: 0.004 - Discrete Fourier Transform - elapsed time: 2 ms
- PASSED - score: 0.899 - Non Overlapping Template Matching - elapsed time: 8 ms
- FAILED - score: 0.0 - Serial - elapsed time: 54 ms
- FAILED - score: 0.0 - Approximate Entropy - elapsed time: 102 ms
- PASSED - score: 0.887 - Cumulative Sums - elapsed time: 4 ms
- FAILED - score: 0.11 - Random Excursion - elapsed time: 28 ms
- PASSED - score: 0.678 - Random Excursion Variant - elapsed time: 1 ms

I thought Chaotic map can generate enough randomness but the result was so frustrating. Is there any logical error inside the code which produce this poor result? I guess the way it generate the bit sequence of the number create the issue.

        if xN <= 0.4:
            bit = 0
        else:
            bit = 1

Is there any better implementation of the chaotic map to produce (pseudo)-random number?

The problem with this random number generator is that the bits are correlated; adjacent output bits differ 70% of the time (of course, for a random stream, we would expect the output to differ 50% of the time). This is enough to cause any test that depends on bit correlation to fail.

This rng is chaos based, but the Lyapunov exponent is not nearly large enough to disguise the correlation between states of consecutive samples.