Error in filter function for VueJs

I want to filter the following in VueJs 2.

My Component is the following:

<template>


        Search <input name="query" v-model="query" class="form-control">

        <table class="table">
            <thead>
            <tr>
                <th>User name</th>
                <th>User email/th>
                <th>Get logs</th>
            </tr>
            </thead>
            <tbody v-for="user in filteredUsers">
            <tr>
                <td> {{ user.firstname }} </td>
                <td> {{ user.lastname }} </td>
                <td> <a v-on:click="getUserLogs(user.user_id)">Show</a> </td>
            </tr>
            </tbody>
        </table>
    </div>
</template>

<script>
    import ConnectionService from '../../components/services/ConnectionService';
    const connectionService = new ConnectionService();

    export default {
        data() {
            return {
                users: [],
                query: '',
                betweenDates: {
                    from: '',
                    to: ''
                },
                logs: {},
                logsVisibility: false
            }
        },

        created() {
            this.getUsers();
        },

        computed: {
            filteredUsers() {
                return this.findBy(this.users, this.query, 'lastname')
            }
        },

        methods: {
            getUsers() {

                this.$http.get(hostname + 'name=person_list&session_id=' + sessionApiId).then(response => {
                    this.users = connectionService.renderMultipleInstances(response.body);
                }, response => {
                    // error callback
                });
            },


            getUserLogs(id) {
                let self = this;

                axios.post('/logs/get_user_logs', {
                        userId: id,                       
                    }).then(function (response) {
                        self.logs = response.data;
                        self.logsVisibility = true;
                        console.log(response.data);
                    });
                },

            findBy(list, value, column) {
                return list.filter(function (item) {
                    return item[column].includes(value)
                })
            }
        }
    }
</script>

I have the following data to filter through it:

users:Array[4095]
    0:Object
        firstname:"Анастасия"
        id:206
        lastname:"Никифорова"
        middlename:"Юрьевна"
        user_id:192
    1:Object
        firstname:null
        id:3362
        lastname:null
        middlename:null
        user_id:2046
...

And error is the following:

[Vue warn]: Error in render function: "TypeError: Cannot read property 'includes' of null"