Why typeahead does not show results?

Question

I use this plugin.

The HTML element is:

<input class="form-control typeahead" maxlength="50" id="secondname" required="required" name="secondname" type="text">

    $("#secondname").typeahead({
        minLength: 3,
        async: true,
        source: function (query, process) {
            return fetchPatientForm({ secondname: query })
                .then((res) => res.data)
                .then((data) => {
                    console.log(data);
                    return process(data);
                });
        },
    });

The response in

 console.log(data);

is:

[{id: 39, name: 'Михаил', secondname: 'Попов', patronymic: '3' }];

So there are no errors and result too. What do I do wrong?

I have tried to return plain array from server like [1, 2, 3] it also does not work