Autocomplete materialize by closing

Question

Friends someone knows how to solve the following problem, the materialize autocomplete, does not show when completing the lenght, but when clicking again on the input it opens and closes quickly without selecting anything, it is being populated with the data, I am using version 1.0.0 of materialize and jquery 3.3.1. Any idea how to solve it? Thank you.

$(document).on('input', 'input.autocomplete', function() {
    let im = $(this).val();
    var base_url = '<?php echo base_url() ?>';
    var url = "<?php echo site_url('/pesquisa/imobiliarias')?>";
    $.post(url, {
        im: im
    }, function(suggestions) {
        var Array = JSON.parse(suggestions);
        var List = {};
        for (var i = 0; i < Array.length; i++) {
            List[Array[i].im] = Array[i].flag;
        }
        $('input.autocomplete').autocomplete({
            data: List,
            limit: 20,
            minLength: 2
        });
    });
});

On the controller:

function imobiliarias(){
    $im = $this->input->post('im');
    echo json_encode($this->Model_pesquisa->imob($im));
}

No Model:

function imob($im) {
    $this->db->select('im');
    $this->db->like('im', $im);
    $this->db->from('entrega');
    $this->db->group_by('im');
    $this->db->order_by('im', 'asc');
    $query = $this->db->get();
    if ($query->num_rows() >= 1) {
        return $query->result_array();
    }
}

On the console.log

{"Cia do imóvel ": undefined, Roca Imóveis: undefined}